CHAPTER EIGHT

MICHAEL LANDWEBER

MALARIA AND AIDS:  THE EPIDEMIOLOGICAL TRANSITION IN THAILAND



Introduction

        Malaria and the Acquired Immune Deficiency Syndrome (AIDS) do not 

seem to have much in common on the surface. Malaria is transmitted by 

mosquitoes; AIDS through contact with bodily fluids. A parasite causes 

malaria; AIDS results from infection with the Human Immunodeficiency 

Virus (HIV). Malaria is curable; AIDS is not. But it is the similarities 

with which this paper is concerned: namely, both diseases have created 

major epidemiological headaches for health professionals around the 

world, and both diseases are preventable. 

        In terms of the health situation in Thailand, these two diseases 

represent the past and the future. As recently as the 1950s, malaria was 

the number one cause of mortality in Thailand. According to most 

estimates, HIV has spread throughout the country to such an extent that 

AIDS will probably become the top killer by the year 2000. The 

juxtaposition of these two diseases will also be utilized to show that 

the policy implemented through the control programs for malaria can 

become a groundwork for dealing with a potentially bigger challenge in 

AIDS. 

        In a broader context, this paper will describe the two 

epidemiological transitions seen in Thailand. The first, a shift in the 

major causes of mortality from infectious to degenerative diseases, has 

already been successfully completed. Malaria will be used as a specific 

example to illustrate this change. The second transition has not yet 

occurred, although it has begun. The sole reason for this predicted shift 

-- from degenerative diseases back to infectious -- will be the rampant 

spread of AIDS. However, it must be noted that this is not a foregone 

conclusion, though based on present statistics and actions taken, it is a 

very probable one. 







Transition Theory

        The starting point for this study is the theory of transitions 

put forward by William Drake in his paper Toward Building a Theory of 

Population-Environment Dynamics: A Family of Transitions. The basic 

premise states that changes within societies, or segments of societies, 

can be viewed in terms of transitions in which a certain aspect of the 

group in question begins in a state of relative stability, passes through 

a turbulent stage marked by change and instability, and finishes at a new 

level of relative stability markedly different from the starting point. 

For this paper on the health situation in Thailand, the epidemiological 

transition from Drakes paper will be used as a framework. 

        The epidemiological transition describes the changing source of 

mortality and morbidity from infectious diseases occurring primarily in 

the younger age groups to degenerative diseases in older age groups.  

This is the traditional way in which this particular transition has been 

viewed. For most countries, passing through this transition marks an 

important step along its developmental road. Within the theory of 

transitions, however, it is important to remember that not all shifts are 

in a positive direction. Every transition has the potential to be 

reversed, or at least to change in a way that negates the previous 

change. This, unfortunately, seems to be what will occur in  Thailand in 

terms of the epidemiological transition. Although the reasons for the two 

transitions are completely different, the result will be the return to 

infectious diseases as the leading causes of mortality, rather than 

degenerative diseases. And again, it will be the young who will be struck 

down as opposed to those who have lived a full life.
The First Transition

        As a nation, Thailand is extremely aware of the state of its 

health. The government has long kept tabs on the various causes of 

mortality and morbidity, and has actively pursued control programs for 

many of the worst offenders. In the case of malaria, it will be shown 

later just how effective such effort can be. In 1987, a commission 

released a report on the health priorities for the country. Within this 

document, the successful passage through the epidemiological transition 

was noted: 

Since the last decade, Thailand has been faced with a different trend of 

health problem. The acute infectious diseases have been declining in both 

number and severity. On the contrary, most non-infectious diseases have 

been steadily increasing.  

A second report written four years later commented that the health 

transition in Thailand began as early as 1975 when the top ten leading 

causes of death changed from the three top-ranked infectious diseases to 

three non-communicable disorders.  

        But, before providing data on the transition and its success, 

consider some statistics about Thailand itself. Situated in the heart of 

Southeast Asia, Thailand currently has a population of around 57 million 

and a population density of approximately 114 people per sq. km. 

Currently, the population is growing at a rate of around 1.27 percent 

annually.  The country is divided into four distinct regions: 1) Central, 

which includes Bangkok and is the most heavily populated; 2) North, a 

mountainous region that is home to Chiang Mai as well as many indigenous 

hill tribes; 3) Northeast, which borders Cambodia and Laos and is 

relatively dry; and 4) South, which has an abundance of coastline and 

islands popular with tourists. Resting in the tropical zone, Thailand has 

two distinct seasons, rainy and dry, although the temperature variation 

is minimal. Most of the population still engages in agriculture to make a 

living. 

        In showing the success of the epidemiological transition, it is 

useful first to examine another common transition (see Fig. 1). The 

demographic transition is characterized by a drop in
Fig. 1: Graph of the demographic transition of Thailand (Source: World Resources Database)



the crude death rate followed soon after by a drop in the crude birth 

rate.  Looking at the comparison for Thailand of these two variables, it 

appears that this trend has already occurred. There are many possible 

explanations for the success of this transition. Often the drop in crude 

death rate is marked by a combination of a decrease in death rates for 

infants and children under five, and an increase in the life expectancy 

for the general population. In a society that relies heavily on 

agriculture, as is still the case in Thailand, the birth rate corresponds 

to the need for individual families to have surviving children to work in 

the fields or the rice paddies. Thus, when infant mortality is high, the 

birth rate is also high to compensate for the loss of children and 

maintain the ability of the family to produce the crops necessary to 

survive. Conversely, as the infant mortality drops, in some cases so does 

the birth rate. In this way the demographic transition is directly linked 

to the epidemiological one. 

        In Thailand, the demographic transition has indeed coincided with 

a marked decline in the infant mortality rate and an increase in life 

expectancy (see Fig. 2). This, in turn, has occurred at the same time as 

the death rates for many childhood diseases have fallen. From this, it is 

not unreasonable to infer that as families see more of their children 

survive, one of the societal results in Thailand has been a move toward 

having fewer children. The purpose of this argument is to show that the 

successful demographic transition can be used as a factor in determining 

the success of the epidemiological transition since the variables in each 

play upon the progression of the other.

        Beyond their application to the demographic transition, the 

variables in Fig. 2 illustrate directly the results of the successful 

epidemiological transition, if not the transition itself. Clearly, as the 

shift has been completed away from infectious diseases that mainly kill 

the young, the statistics for infant mortality and deaths for children 

under five years of age have fallen dramatically. At the same time, life 

expectancy has increased as the mortality rates begin to be dominated by 

diseases and conditions that characteristically strike the elderly. 

        This methodology so far may seem indirect. After all, if one 

wants to chart the epidemiological transition, it might seem sufficient 

to put the death rates for infectious diseases on a graph with those for 

degenerative diseases. Unfortunately, the availability of disease 

statistics for Thailand make this straightforward approach nearly 

impossible. For the most part, the statistics for this study were 

obtained from two sources: the World Health Organization and the 

International Medical Foundation of Japan. Although each of these 

organizations received their numbers from the Thai government originally, 

there are still occasional discrepancies between the two. Whenever 

possible, this paper will refer to statistics taken directly from Thai 

government reports. However, since most statistics were gathered from the 

aforementioned secondary sources, discrepancies will be noted when they 

are deemed important or necessary.
        Fig. 2: Comparison of life expectancy and mortality of children 

under five in Thailand. The left axis corresponds with life expectancy; 

the right axis corresponds with mortality - Under 5 and mortality - 

infant. (Source: World Resources Database).



        One other peripheral set of statistics should be acknowledged 

prior to considering the disease statistics. Health facilities are 

widespread throughout Thailand, and this has been a major factor in the 

successful epidemiological transition. Thailand is divided into 73 

Provinces, which in turn are broken down into 621 districts, which 

further segment into 6283 tumbons. As of 1985, 86% of the districts had a 

major hospital; however, every tumbon had a health center.  This 

extensive coverage will become important when looking specifically at the 

containment of malaria and AIDS. Additionally, the widespread access to 

health care accounts for the percentages of 1-year olds who have had 

certain immunizations (Fig. 3). Of course, this immunization strategy 

influenced the epidemiological transition since these diseases rank among 

the major childhood illnesses.
        Fig. 3: Percentage of children receiving major immunizations in 

Thailand. (Source: World Resources Database). 



Mortality Statistics

        It is immediately clear (Table 1) that the leading causes of 

death in Thailand have shifted from infectious diseases to degenerative 

diseases over the past forty years. One distinction between infectious 

and degenerative diseases that is often made involves degree of 

preventability. Infectious diseases -- such as malaria, tuberculosis, 

pneumonia, etc. -- are often labeled as more preventable than their 

degenerative counterparts -- heart disease, cancer, cirrhosis. However, 

this is a troublesome distinction since it can be said that many 

degenerative diseases are preventable. To clarify, preventable in this 

case refers mainly to societal and governmental variables, such as access 

to health care, sanitary facilities and clean water. This is still not 

adequate considering that environmental factors that are subject to 

government intervention are often considered causes of many degenerative 

diseases. However, for this study, it will suffice to leave the 

distinction fuzzy, but noted.
Rank 1950 1960 1970 1980 1990
No. 1 Malaria 
195
Gastroenteritis 
38.7
Accidents 
27.2
Accidents 
35.9
Heart Disease 
49.6
No. 2 Tuberculosis 
65.5
Tuberculosis 
34.7
Tuberculosis 
20.8
Heart Disease 
31.4
Other Accidents25.3
No. 3 Gastroenteritis 
65.1
Pneumonia 
32.5
Diarrhea 
17.6 
Cancer 
23.6
Cancer 
22
No. 4 Pneumonia 
39.4
Malaria 
30.2
Heart Disease 
15.3
Tuberculosis 
14.3
Diseases of the Digestive System 
18.4
No. 5 Dysentery 
32.8
Heart Disease 
19
Pneumonia 
14.8
Pneumonia 
10
Transportation Accidents 
15.2
        Table 1: List of the top five causes of mortality in Thailand 

over the years. The number below the cause indicates the number of deaths 

per 100,000 population. A note of further clarification: on this chart 

the term malignant neoplasms has been changed to cancer. The source 

designated these particular death rates as malignant neoplasms of other 

sites. The reason for this distinction is unclear. In 1990, the death 

rate per 100,000 for all malignant neoplasms, or all types of cancer, was 

39.3, which would move it to second on the list for that year. (Source: 

International Medical Foundation of Japan). 



        Another interesting comment about the leading causes of death 

revolves around the increased prominence of accidents. In fact, by 1987 

injuries as a category -- which includes accidents, homicides and 

suicides -- accounted for more deaths than either infectious diseases or 

degenerative diseases.  However, this is not directly relevant to the 

epidemiological transition.

        The table of leading causes of death shows a marked decline in 

death rates of some of the major infectious diseases. Tuberculosis, for 

instance, fell from 65.5 deaths per 100,000 population in 1950 to 14.3 

deaths per 100,000 in 1980. By 1990, it had dropped out of the top five, 

but Figure 4 illustrates that its mortality rate has continued to 

decline. Similarly, the death rates for pneumonia plummeted over the 

years. Malaria demonstrates the most striking example of the control of 

an infectious disease and will be discussed in detail later. 

        The table also illustrates the increase in degenerative diseases. 

It is unclear whether or not a significantly higher percentage of people 

contract these diseases now or whether the higher rates

 

        Fig. 4: Mortality rates for selected causes in Thailand. Data for 

1987 was generated using statistics from other years and trends. (Source: 

International Medical Society of Japan).



are simply a function of an increase in the older population prone to 

such ailments. The important factor to note is the increased prominence 

of degenerative diseases among the leading causes of death. Still, heart 

disease in 1990, which was responsible for 49.6 deaths per 100,000, 

cannot be compared to malaria in 1950 at an incredible 195 deaths per 

100,000. This is another sign of the successful epidemiological 

transition. No longer does a single disease run rampant through the 

society, causing great numbers of deaths. Mortality in post-transition 

Thailand has become widely distributed with no single cause reigning 

supreme, but with degenerative diseases at the forefront.

        However, despite the dramatic improvement in death rates for 

infectious diseases, morbidity rates still remain quite high in Thailand. 

Again, malaria is probably the clearest example of the success of 

controlling mortality, while being unable to conquer morbidity. In the 

tropical climate, it has proven extremely difficult to eradicate 

infectious diseases. It might be more accurate to say that the 

epidemiological transition in Thailand concerns the control of infectious 

diseases as a source of mortality. However, as the following discussion 

of malaria control over the past fifty years will show, infectious 

diseases may never be effectively limited as a source of morbidity. 



Malaria Control in Thailand

        In 1949, malaria accounted for 205.5 deaths per 100,000 

population in Thailand, killing 38,046 people.  By 1992, the death rate 

had fallen to 1.8 per 100,000 population for a total of 1,051 dead.  

These tangible results have been the result of better access to health 

care, which in turn has led to an increased distribution of anti-malarial 

drugs. Before tracing the course of malaria control programs in Thailand 

over the past few decades, it must be noted that the number of cases of 

malaria have not marked the same continual decline as the death rate 

statistics. In fact, morbidity for malaria has fluctuated since the 

mid-seventies (Fig. 6). The reasons for the difficulty in maintaining low 

levels of morbidity will become evident during the recounting of the 

history. However, the morbidity statistics do highlight the difficulty of 

obtaining accurate statistics about malaria. The World Health 

Organization recorded consistently higher numbers of cases than the 

Japanese medical association. There are many reasons why this might 

occur, all of which are factors in the spread and continued prevalence of 

the disease. One organization might be including cases from among the 

large number of workers who enter Thailand from neighboring countries to 

work. Additionally, migration of Thai workers within the country makes it 

difficult to obtain an accurate count, since many of these people end up 

traveling in areas where malaria is highly endemic. One other possibility 

may involve the problems of determining the number of cases within the 

indigenous hill tribes of the Northern region.

        The ecosystem of malaria consists of three interacting organisms: 

human beings, mosquitoes and the parasite that causes the disease. The 

parasite is carried by the mosquitoes, which in turn infect human beings. 

Mosquitoes can also receive the parasite from infected people, thus 

increasing the diseases chances of spreading. Thailand has 62 species of 

mosquito that are capable of transmitting the disease; however, two 

species are the primary carriers.  Because of its extensive rainy season, 

Thailand has many areas that become ideal breeding grounds for the 

insects. There are three types of parasites that are predominant in 

Thailand. Of these, increasing attention is being paid to P.Falciparum, 

which has shown high levels of resistance to many of the known treatments 

for the disease. Malaria has been eradicated in the major cities of 

Thailand. However, in rural areas throughout the country, malaria remains 

a problem.

        Thailand began a concerted effort to control malaria in 1930 when 

the first Malaria Unit was formed in Chiang Mai to perform surveys, 

distribute medication and educate the general populace. In 1949, the 

first spraying of DDT inside houses occurred in Chiang Mai province in an 

effort to control the mosquito population and thus prevent transmission 

of the disease. At the same time, the distribution of anti-malarial drugs 

increased for use as both prophylactics and treatment. This two-pronged 

approach of attacking both the parasite and the mosquito, which is 

followed in

 

        Fig. 5: Mortality rates for malaria. Data for 1987 was 

unavailable. (Source: World Health Organization, 1949-1985; International 

Medical Foundation of Japan, 1986-1992).



 

        Fig. 6: Malaria morbidity statistics for Thailand. The vertical 

axis represents the number of cases; the horizontal axis represents the 

year. (Sources: International Medical Foundation of Japan and the World 

Health Organization).
most malaria control programs, yielded positive results almost 

immediately, as noted by the World Health Organization: 

Encouraged by the rapid reduction of malariometric indices in the pilot 

project area with residual insecticidal spray, the Government of Thailand 

decided to launch a nation-wide malaria control programme which was 

extended in a phased manner. Along with spray operations, for purposes of 

evaluation, malariometric surveys were carried out at quarterly 

intervals, and termed as a surveillance system. In addition, malaria 

mortality statistics were also collected.  

This widespread household spraying did in fact have an immediate effect 

on the prevalence of malaria cases. One interesting question that will 

not be covered in this paper is the effect on the Thai population of 

having a toxic insecticide such as DDT sprayed inside homes. However, 

ignoring the possibility that the insecticide might be harming the 

general public, Thailand pressed ahead. In 1965, the government 

implemented a malaria eradication plan for the nation with the goal of 

conquering the disease altogether. 

        Their optimism proved to be premature. In a single year, between 

1969 and 1970, the number of cases of malaria increased by 42 percent.  

There are many reasons for the increase, but perhaps the two most 

important reflect the adaptability of the mosquito and the parasite. 

Before spraying became widespread, mosquitoes usually fed on people 

inside their homes. Soon after spraying it became evident that the 

mosquito population was avoiding the DDT-sprayed houses, yet continuing 

to bite people outside where there was no concentration of insecticide. 

At the same time, the parasite was displaying an increasing rate of 

resistance to the prevalent treatments. 

        Throughout the seventies, morbidity continued to fluctuate, even 

as the mortality rates continued their downward trend. In 1982, a new 

health plan for the nation included the aim of integrating malaria 

control into primary health services. The result has been a cohesive 

local approach that covers the entire country. 

Spraying was done by the village spraymen. Blood slides were collected by 

the health centre staff, by malaria volunteers and health volunteers. 

There is one malaria volunteer in each village in addition to health 

volunteers. Health education was being done by health communicators. 

There is one health communicator for a group of 10-15 houses.  

Such an organized and pervasive approach holds the key to the second 

transition and eventually control of AIDS. 



Controlling Human Behavior: Prelude to the Second Transition

        As has been mentioned, reducing morbidity of malaria has posed a 

far greater challenge than reducing mortality. While the adaptability of 

mosquitoes and parasites play a major role in this challenge, the human 

factors are more important to examine for this paper. The government can 

-- and, in Thailand, does -- provide access to health care and 

medication, offer household spraying, and educate the public about the 

disease. But it is the responsibility of the general public to take 

advantage of these services. One factor in the continued morbidity is the 

refusal of many to have their houses sprayed, or to sleep under a 

mosquito net or near a mosquito coil. If the people do not follow the 

advice of the health professionals, it makes controlling the disease more 

difficult. 

        In the case of malaria, other human factors also contribute to 

the spread and perpetuation of the disease. Migrancy is a common 

occurrence in Thailand as a significant segment of the population moves 

around from place to place to work. These people not only lack immunity 

to local strains of parasites, but also introduce new strains into the 

area. Therefore, migrant workers are likely to become infected in the new 

area as well as help to infect the local population. This problem is 

compounded by foreign workers who introduce parasite strains from other 

countries. Another problem occurs with the improvement of the 

infrastructure and what might be called economic progress. Two examples 

are the building of dams and deforestation for timber. The first 

increases the breeding grounds for mosquitoes; the second brings the 

human population into contact with mosquitoes and parasites previously 

out of range. Both increase morbidity. One final challenge to malaria 

control are refugees, a common phenomenon among the often politically 

unstable countries of the region. For example in the early 1980s, 

Thailand became home to half a million people fleeing Cambodia. Although 

mosquito controls were implemented at the refugee camps, an increase in 

malaria was almost inevitable with the mixing of local and foreign 

parasites. 

        So what are the policy implications of the history of malaria 

control and what path should be followed in the future? It has been shown 

that control of morbidity is a nearly impossible proposition. Mosquitoes 

are a fact of life in Thailand; the only way to get rid of them would be 

to completely destroy their environment. No one is advocating razing the 

forests; at least, not for the purpose of mosquito control. Morbidity 

will fall naturally, and already is, as the economic progress of the 

country begins to reflect itself in higher employment rates, less 

migrancy and better housing. The best policy route, besides continuing 

education on avoiding being bitten by mosquitoes, is to follow the road 

already taken toward better health service nationwide.

        It is the difficulty of controlling human behavior that leads to 

the second epidemiological transition in Thailand and AIDS. Malaria has 

human behavioral factors involved in its spread, but reducing the 

mortality rate does not rely on controlling these. For malaria, the 

government can afford to concentrate on those areas on which it can have 

a definite impact, while allowing behavior control to be a secondary 

concern. The second transition, however, requires that Thailand take 

exactly the opposite approach:

One cannot compare AIDS to diseases such as cholera and malaria, which 

currently claim the lives of more people. AIDS reaches further into 

society than these diseases because (a) it affects people during their 

most productive years in which they are typically responsible for the 

care and support of both children and elderly parents; (b) transmission 

of the virus generally goes unrecognized; and (c) no cure is available, 

and probably will not be during this century.  

Instead of treating those who have the disease as the first priority, 

AIDS must be prevented from spreading by changing the behaviors of the 

populace that lead to the transmission of HIV. AIDS cannot be cured once 

it is contracted; people with the HIV almost inevitably will develop 

AIDS. It is crucial to stop the transmission at the source.



The Second Transition: AIDS

        One of the most interesting, and terrifying, aspects of AIDS is 

the speed with which it is able to spread through a population, if the 

conditions are favorable. As will be shown, Thailand has proven extremely 

hospitable to the HIV virus. Unlike malaria, health officials know 

exactly when the first AIDS victim appeared in Thailand and are able to 

trace the entire course of the disease to date.

The first case of full-blown AIDS was reported in Thailand in August 

1984. The patient was a 28 (sic), bisexual male and had just returned 

from the United States where he had spent 2 years. He was hospitalized 

there and then returned home where he received additional care. He died 

by the end of 1984. Due to this alarming event, serological 

investigations of the high risk group were begun that year.

        The second reported case, in December 1984, was a homosexual 

foreigner who returned home after a short period of stay. In 1985, 4 more 

cases were reported. Three are foreigners, who had acquired infections 

abroad. The only Thai patient was a 27 year old bisexual male who had 

contracted the disease from a German who visited Thailand every 2 to 3 

months. The patients female partner was also infected and was classified 

with HIV as ARC (AIDS-related complex).  

As was the case in many countries, the initial appearance of AIDS led to 

stigma. In Thailand, AIDS was viewed as a foreign disease transmitted 

through homosexual contact. However, at the same time, the health 

community in Thailand proved itself less short-sighted than some 

countries, acknowledging that the disease would spread.

Asymptomatic carriers are more likely to spread the disease. Without 

serological examination, they do not differ from the general population. 

The total number of asymptomatic carriers is not known, however, the 

average incidence of seropositives among the high risk population (i.e. 

homosexual/bisexual men, female prostitutes, persons who received blood 

transfusions and intravenous drug abusers) in four seroepidemiological 

surveys conducted in Bangkok and Pattaya ranged from 0.6 to 2.4 percent. 

This nod to the HIV virus showed the willingness to admit that the 

disease was hidden among the population. 

        By 1988, the government had recorded a total of 3,138 carriers of 

the HIV virus, 38 of whom had developed symptoms of some sort.  Clearly 

there were many more: by 1994, more than triple that number had 

full-blown AIDS (See Fig. 7). The Thai Ministry of Public Health 

estimated that between 500,000 and 600,000 Thais were infected with HIV 

by 1993.  Projections have been done that estimate that, without 

significant changes in behavior among the populace, there will be between 

3.4 and 4.3 million Thais infected by the year 2000.  This is a 

staggering prediction considering that within ten years of being infected 

with the HIV virus more than 67 percent of people are expected to develop 

AIDS and die within the next two years.  Using this framework and the 

Ministry of Public Healths current estimate of HIV carriers, it can be 

inferred that by the year 2003 an additional 335,000 people will develop 

AIDS and probably die by the year 2005. Even dividing this number of 

deaths over 10 years would still mean approximately 33,500 deaths a year 

or a mortality rate of 55.8 per 100,000. Referring back to the leading 

causes of mortality shows that AIDS will clearly take over as the leading 

killer, even without the truly apocalyptic predictions.
        Fig. 7: New cases of AIDS reported in Thailand annually. Cases of 

AIDS-related complexes -- conditions linked to the HIV virus and its 

weakening of the immune system -- have not been included, since 

statistics for these are sketchy and unreliable. (Source: International 

Medical Foundation of Japan and the World Health Organization). 



        Although Thailand currently appears to have the worst AIDS 

problem within Asia, it must be noted that South and Southeast Asia as a 

whole currently sits on the brink of a major health crisis. Cases 

throughout the region have been increasing at an exponential rate (see 

maps). According to the World Health Organization, as of the middle of 

1993, more than 1.5 million people in the region were infected with HIV.  

Because AIDS strikes those in their prime working years, the epidemic is 

also expected to have a devastating effect on the economic growth that 

has skyrocketed throughout the region in recent years. This topic, 

however, is to large to be handled satisfactorily in this study. 

        As noted, the first cases of AIDS were attributed to homosexuals 

and foreigners. Following the lead of other countries, Thailand first 

focused their efforts on gay men, prostitutes and intravenous drug users. 

The last two groups in particular have been responsible for much of the 

spread of the disease, although it is now clear that the disease is 

spread primarily through heterosexual contact (Fig. 8). However, to 

understand why the heterosexual population became the focus of 

transmission so rapidly, two societal issues must first be addressed: the 

drug problem and the thriving sex industry.
Map 1.
Map 2.
Map 3.
Map 4.
        Drugs, particularly opium, have always been present in Thailand. 

The Golden Triangle area, which encompasses the far northern part of 

Thailand as well as parts of Burma and Laos, 

currently accounts for a large portion of the heroin trade worldwide. In 

the early 1980s, Thailand saw a sudden increase in heroin addiction, 

particularly among young men living in urban areas. In terms of AIDS, the 

most important factor was the sharing of needles used to inject heroin. 

One study showed that in Bangkok in 1982 between 82 and 92 percent of 

heroin users took the drug intravenously.  In 1988, a seroprevalence 

survey of drug users was taken at clinics in Bangkok. The first survey 

taken between January and March determined a rate of 15.6 percent 

HIV-positive; just six months later that already high rate had risen 

sharply to 42.7 percent. 

        Recognizing the problem, drug clinics, particularly in Bangkok 

where the number of addicts was highest, began to integrate AIDS 

awareness and prevention into their programs. Demonstrations on how to 

properly use condoms and clean needles with bleach became common. The 

clinics now provide a number of treatment options ranging from a 45-day 

detoxification course. . . to promoting safer ways of administering 

heroin (e.g. by smoking), to meditation to reduce the need for a chemical 

high.  

        While the drug problem has posed serious challenges in the 

control of AIDS, by far the most serious obstacle to limiting the spread 

of the disease is Thailands widespread sex industry. Most intravenous 

drug users are found in Bangkok and parts of the north. Prostitutes are 

found virtually everywhere in Thailand. Some estimates on prostitution 

place the number of sex workers in Bangkok between 100,000 and 200,000 

with as many as 800,000 for the entire country. 



        Fig. 8: Method of transmission in Thailand of  HIV based on the 

category of the person who causes the infection. Abbreviations: 

Het.-Heterosexual; Hom.-Homosexual; Bi-Bisexual; IDU-Intravenous Drug 

User. The term vertical refers to children who have been infected through 

their mothers. (Source: Thai Ministry of Public Health, 1994). 

 

A survey done in June 1991 found that 24 percent of brothel prostitutes 

were HIV-positive. The same survey showed that in northern provinces, 

which do not include Bangkok, this rate was over 40 percent. 

        Attitudes toward sex and prostitution in Thailand pose the 

biggest threat to controlling the AIDS epidemic. Thai men regularly go to 

prostitutes for sex. One survey showed that 44 percent of Thai men lost 

their virginity with a prostitute at an average age of 18.  Another group 

of surveys found that 75 percent of all Thai men have had commercial sex 

at least once in their lives, 16 percent within six months of the 

survey.  Many of these men contract the virus and then go home to their 

wives. This connection between commercial sex and infection between 

spouses illustrates another aspect of prostitution in Thailand:

The circle may be especially vicious because of a peculiarity of Thai 

prostitution. There are many male prostitutes as well as female ones. The 

men who service foreigners tend to be heterosexual by preference, and 

often have wives and girlfriends (some of them prostitutes too) to whom 

they pass the virus. This creates a frighteningly wide channel of 

transmission between the homosexual and heterosexual pools. 

Two other factors increase the frequency of transmission within families. 

First, homosexuality does not carry the stigma in Thailand that it has in 

Western countries; many married men will have sex with male prostitutes. 

Also, prostitutes who charge lower rates and cater to average Thai men, 

rather than rich locals and foreigners, tend to have a higher incidence 

of the HIV virus. According to a government seroprevalence survey done in 

1991, only five percent of prostitutes charging high rates were 

HIV-positive, as compared to 20 percent of those charging low rates.  

These lower paid prostitutes are also more likely to engage in sexual 

activity with more clients in a single day than higher paid sex workers. 

        All of this leads to one of the more tragic aspects of the AIDS 

situation in Thailand: the infection of children through their mothers. 

One prediction posits that as many as three million children will be born 

to HIV-positive mothers during the onset of the next century; of these, 

one million will probably die of AIDS while the rest will probably end up 

orphans.  This, in turn, will place an incredible economic burden on 

Thailand as a whole.

        Because of the danger involved, the most obvious policy route 

would appear to be a nationwide crackdown on prostitution. Brothels 

operate very openly in Thailand and arrests for prostitution are 

infrequent at best. There are two reasons for this: corruption and 

tourism. The first is seen mostly on a local level. The sex industry 

provides an economic engine for many segments of the country, from which 

many local officials and businesses profit. Breaking this cycle of 

corruption is a daunting prospect. 

        Policy toward prostitution on the national level does not help 

matters either, since it is intertwined with the booming tourist 

industry. Thailand has become one of the most popular tourist 

destinations in Asia, helped in part by the lure of the sex industry. It 

is a telling coincidence -- or possibly not a coincidence -- that 1987 

was declared Visit Thailand Year, and 1989 officially became the Year to 

Combat AIDS. Patphong Road, one of Bangkoks foci for the sex trade, is 

often visited by busloads of tourists. Two-thirds of the visitors to the 

country as of 1992 were male, and there still are organized sex tours 

from Japan, Taiwan, South Korea, Australia, the United States and 

Europe.  The foreigners create two problems: the possibility of bringing 

HIV with them from their home country, and the likelihood that they will 

export it back with them. Though it is not certain how many of these 

tourists actually engage in sexual acts with prostitutes, the surge in 

tourism still initially made the Thai government reluctant to discuss the 

problem of AIDS, for fear of scaring away foreigners and their money. 

        Despite the governments early reticence, the full scope of the 

problem has now been acknowledged, including its connection to tourism. 

The Thai government has initiated a full-scale plan to combat AIDS, 

including public service announcements and condom distribution. The 

government distributed 70 million condoms in 1991 alone.  Another aspect 

of the program has been to increase the scope and availability of testing 

for the HIV virus. However, reports are mixed as to whether or not 

condoms are used in commercial sex. In the minds of foreigners and Thai 

men, Thai women, especially prostitutes, are expected to be subservient 

and eager to comply with their wishes. Brothel owners propagate such 

thought with the bottom line being that the decision to use a condom 

rests with the client, not the prostitute. 



The Effects of the Second Transition

        It is clear that if drastic changes are not made in behavioral 

patterns that AIDS will become a major cause of mortality in the coming 

years. In fact, based on number of people starting to come down with 

full-blown AIDS, it seems that it is already inevitable that many will 

die: the key now is to keep some control over the situation. In looking 

at AIDS in terms of a second epidemiological transition -- the shift back 

to infectious diseases -- the basic nature of the disease must be 

acknowledged. AIDS weakens the immune system. This, in turn, increases 

the vulnerability to opportunistic infectious diseases. Although the 

death rates for other diseases, such as tuberculosis, have not yet 

increased, it is to be expected that they will as the number of AIDS 

cases goes up. This will lead directly to the second transition. 

        The effects of this transition on the country will be widespread. 

Domestically, a shortage of labor, both in quantity and quality, may 

occur with an increase in AIDS. High rates of absenteeism brought on by 

illness will certainly be disruptive to companies. Finding workers to 

replace those that have died will be difficult and costly.  Health care 

costs will skyrocket as more and more people begin to get sick. There 

will also be great expense, both sociologically and financially, due to 

the large number of children whose parents will die. Looking at many of 

the variables that this study used to show the successful completion of 

the first transition, the U.S. Department of Commerce made projections 

for the year 2010 with and without AIDS for Thailand. It predicts that, 

if the disease runs the course it is currently on, infant mortality will 

more than double and child mortality will quadruple. Life expectancy at 

birth will fall from around 75 years to closer to 45. Finally, the 

population growth rate will go from being positive to negative. 

        Predicting the number of people who will die of AIDS in the 

coming years is a particularly difficult proposition. There are too many 

factors that affect the spread of the disease and too many unknowns among 

the current population (i.e. the number of HIV-positive Thais). However, 

Figures 9 and 10 show the results of using two basic methods of creating 

projections on the current number of AIDS deaths. As can be seen, the two 

projections differ wildly. The linear projection presents an unrealistic 

picture of the future, with AIDS deaths rising slowly, but steadily, over 

the next two decades. Although it is probably too drastic, the 

exponential projection in Figure 10 is also, unfortunately, more 

accurate. The projection only works until the year 1998, after which the 

number of AIDS deaths for the nation exceeds the total population. It 

should be noted that this dire prediction is based on the number of 

deaths for 1990-92. The curve would undoubtedly be even steeper if data 

from the last two years was available since the number of deaths will 

have gone up. This projection is not useful as a pragmatic tool for 

dealing with the epidemic logistically. It is nearly unthinkable that 

more than 20 million people, nearly half of Thailands population, will 

die of AIDS in 1998. However, this curve is extremely important to note 

because of the rapid increase that takes place in a very short span of 

time. Up until the projection for this year, the curve is
        Fig. 9: Linear projection of AIDS deaths based on 1990-92 

statistics. Year one corresponds with 1990; year 21 is a prediction for 

the year 2010. (Source: International Medical Foundation of Japan).



        Fig. 10: Exponential projection of AIDS deaths for Thailand based 

on 1990-92 statistics. Year 1 corresponds to 1990; year 9 corresponds to 

1998. The projection for deaths in the year 1999 exceeded the population 

of Thailand, and therefore has not been included. (Source: International 

Medical Foundation of Japan).
relatively flat. Suddenly, in 1996, the number of deaths skyrockets. 

While the reality will not mimic these particular numbers, it is almost 

certain to mirror the trend. As has already been shown through the 

dramatic increases in both the number of cases of HIV and full-blown 

AIDS, within the next two decades the curve seen in the exponential 

projection will become the unfortunate reality.

        However, another type of projection is more useful in terms of 

setting a timetable for policy within Thailand. Using a logistic curve 

fit with an upper limit, it is possible to avoid the pitfalls of the 

exponential and linear graphs. By setting an upper bound, the projection 

maintains a limit without sacrificing the ability to view the general 

trend, which in the case of AIDS and HIV infection is quite dramatic. In 

order to do these projections, it must be noted that two statistical 

references were needed. For the projection of HIV infections (Fig. 11), 

the two data points used were the Thai government estimate of 500,000 

cases in 1993 and the projection cited of a possible 3.4 million people 

with the virus by the year 2000. The graph of AIDS deaths (Fig. 12) was 

extrapolated from the same numbers, using the 67 percent formula cited 

earlier. Of course, it must be acknowledged that basing a projection on 

numbers acquired, respectively, from an estimate and a projection gleaned 

from  other sources is not the ideal situation. Still, while the actually 

numbers may be debatable, the trend shown can not be ignored. 

        The upper limit for the two graphs provided was set at 7 million, 

a rather arbitrary doubling of the HIV infection statistic for the year 

2000. Although these are the only projections included in this paper, a 

number of other options were calculated using upper bounds ranging from 5 

million to 56 million, the entire population of the country. It is 

important to consider the upper limit set as a worst case scenario, the 

total number of people that might contract the disease. In experimenting 

with the limit, an interesting phenomenon was found. Regardless of the 

worst case scenario envisioned, the HIV projections showed that it would 

come to fruition around the year 2010, give or take a few years. In other 

words, no matter how many people are believed to be at risk from 

contracting HIV, the projection predicts that with the current trend very 

nearly all of them will have it by the year 2010. Not surprisingly, the 

AIDS graphs with various limits also showed striking similarity in shape 

and end point, predicting that deaths will peak around the year 2020. 

Though it is impossible to say how many people will contract HIV or 

eventually die from AIDS, these projections provide policy makers with a 

framework in which to plan for the epidemic at hand.
        Fig. 11: Logistic projection of HIV infections in Thailand with 

an upper limit set at 7 million. Year 0 (not shown) is 1993. Year 33 is 

2026. 





        Fig. 12: Logistic projection of AIDS deaths in Thailand with an 

upper limit set at 7 million. Year 0 (not shown) is 1993. Year 31 is 2024.

 

Conclusion

        Unfortunately, the outlook for Thailand from a health perspective 

is bleak. As was mentioned earlier, the second transition is not a 

foregone conclusion, but the statistics make it appear very likely. To 

make matters worse, death rates for AIDS in Thailand still barely 

register among the leading causes of mortality -- only 248 people died of 

AIDS in 1992.  Of course, the low number of deaths in itself is not a bad 

thing, but it presents a misleading picture of what is really happening. 

Just as the number of cases has shot up dramatically in the past couple 

of years, so will death rates in the next two or three, as seen in the 

projections. It is inevitable because AIDS is incurable. There is always 

the hope of a cure, a medical breakthrough. Currently, the World Health 

Organization lists over 150 experimental drugs and at least 13 vaccines 

undergoing testing worldwide.  A cure would almost immediately end the 

epidemic, assuming it was not reserved for those able to pay for it, and 

make the second transition nothing more than a theory. But this type of 

dream -- and currently it is just that -- combined with the low death 

rates in Thailand serve to do nothing except become misleading arguments 

against drastic action. 

        So what are the policy implications for AIDS? For this, the first 

place to look is at the malaria control program. Every tumbon should have 

an AIDS volunteer, just as there is a malaria volunteer. This person, or 

group of people, should be responsible for making sure that all local sex 

workers are educated about AIDS, that condoms are widely distributed and 

that regular testing occurs. Thailand has already proven itself capable 

of providing health services nationwide. Now AIDS education and treatment 

must become part of primary care just as malaria has. 

        The second policy implication will be far more difficult to 

enact, let alone enforce: a change in attitude toward sex and women among 

Thai men. Brothel owners must allow prostitutes to insist on condom 

usage. Thai men must be convinced not to patronize brothels or, at least, 

not to engage in unsafe sex. Changes such as these do not fall easily 

into a government plan of action; it is nearly impossible to legislate 

respect for women. One way to obtain greater control over the spread of 

AIDS within brothels would be to legalize prostitution and then regulate 

it. This would undoubtedly be a controversial proposition, though there 

are probably fewer societal impediments than in other countries. If the 

government were enabled to license and monitor brothels, it would also be 

able to mandate condom usage and limit the number of prostitutes allowed 

to work. Of course, as is always the case, governmental control would 

bring a whole new set of problems without necessarily solving the 

original ones. 

        There is one guarantee. Attitudes towards sex among the general 

population will change, just as they did in the homosexual and drug user 

communities in Thailand, as people begin to see those around them die. 

Unfortunately, in Thailand that may be the only way that sexual habits 

will change and the AIDS epidemic will be slowed. Sadly, it seems, based 

on this, that the second epidemiological transition will occur with 

devastating consequences. This is what the Thai government must be 

prepared for, the worst case scenario as seen in the logistic 

projections. While it does everything in its power to try and convince 

people to change their behavior, the government must be ready to deal 

with the health crisis that will come if it fails to achieve this 

original goal. The timetable can be seen in the graphs (Fig. 11 and Fig. 

12). The attempts at prevention must be fully implemented immediately 

because it is in the next ten years that the majority of HIV infections 

will occur. Looking ahead, policy makers must plan for a dramatic 

increase in the number of AIDS sufferers between the years of 2010 and 

2020. This is not too far in the future, and all sectors of the 

government must have plans to deal with the problem in the event that the 

worst case scenario should come to pass.
Notes
References (a) (b)