Maternal Health Care and the Spread of AIDS in Burkina Faso. Eva Deuchert, University of Freiburg

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1 Maternal Health Care and the Spread of AIDS in Burkina Faso Eva Deuchert, University of Freiburg Abstract: The present paper argues that the poor quality of obstetric services contributes to the spread of HIV. Using data from Burkina Faso, the paper shows that tetanus toxoid injections are positively associated with a higher risk of HIV infection. This suggests that HIV transmission occurs in the health care sector (most likely by unsafe injection practices). Providing training and sterile equipment can greatly improve the quality of maternity health care settings and thus, significantly reduce number of new infections. In addition, patients should be informed about the risk of unsafe injection practices. This allows taking protective actions against infections with unsterile needles. Keywords: AIDS, HIV, injections, maternal health care 1. Introduction In 2005, estimated 40.3 million people are infected with the Human immunodeficiency virus (HIV), more than 60 percent are living in Sub Saharan Africa. 3.2 million people in Sub Saharan Africa became newly infected and 2.4 million died from causes related to HIV/AIDS (UNAIDS 2005). The reason why Sub Saharan Africa is disproportionately vulnerable to HIV is subject of a controversial debate. HIV transmission occurs through direct contact with contaminated body fluids (blood, semen, vaginal fluid or breast milk). The transmission modes are unprotected sexual contacts, vertical transmission from mother-to-child, the use of contaminated needles and sharp instruments (tattooing, needle sharing, needlestick injuries, re-use of needles, syringes, and surgical instruments) and blood transfusion. It is widely asserted that HIV is predominantly heterosexually transmitted in Sub Saharan Africa (Schmid et al. 2004). Varying HIV prevalence rates in Sub Saharan Africa are explained by differences in sexual behaviors (Philipson and Posner 1995, Caldwell 2000), sexual network patterns (Morris and Kretzschmar 1997) and differences in transmission efficiencies through different levels of male circumcision (Auvert et al. 1

2 2001) or untreated sexually diseases (Oster 2005). However, in contrast to the hypothesis that heterosexual transmission is the dominant transmission mode in Sub Saharan Africa, Gisselquist and colleagues (2002, 2003) argue that unsafe medical care, particularly the re-use of contaminated syringes and needles, is responsible for the Sub Saharan HIV/AIDS epidemic. Numerous studies provide empirical evidence for the correlation between exposure to the medical system and HIV infection in Sub Saharan Africa. Increased risk of HIV infection is associated with increasing number of injections (Quigley et al. 1997, 2000; Bloom et al. 2002). Furthermore, several empirical studies relate higher risk of HIV to the maternal health care system. Chao and colleagues (1994) show that women who received assistance by medical personnel at last delivery are almost 3 times more likely to be HIV positive compare to women with unassisted delivery. Gray and colleagues (2005) report increasing risk of HIV acquisition during pregnancy, which cannot be due to sexual transmission. However, reverse causality hampers the interpretation of the studies mentioned above, since HIV positives are more likely to be ill these injections may have been administered for the treatment of HIV related illnesses (Schmid et al. 2004). Thus, it remains unclear, in how far unsafe medical care contributes to the spread of HIV in Sub Saharan Africa. The present paper provides further evidence on the impact of health care services on the risk of HIV infection. Using data from the 2003 Demographic Health Survey from Burkina Faso, the impact of receiving tetanus toxoid injections on the risk of HIV infection is examined. Focusing on data about tetanus injections has two major advantages. Querying about a specific injection may improve participants recall (Sudman et al. 1996). More importantly, since these injections are given for the prevention of neonatal tetanus and not for the treatment of HIV related illnesses, the causality problem postulated by Schmid and colleagues (2004) may not arise. However, HIV infected women are more likely to be in contact with the formal health sector (for instance because they search for treatment), and once in contact with the health care sector they may become more likely to immunize their children. The present paper addresses this problem by employing a two-stage residual inclusion approach using spending capacity (wealth, education) and distance to the next health facility as 2

3 instruments. It is shown that receiving tetanus toxoid injections significantly increase the risk of HIV infection. The information gathered from this analysis can help to design public health interventions, which are aimed to cost-effectively prevent new HIV infections in Burkina Faso. The remaining sections of the paper are organized as follows. Section 2 provides information on the formal health care sector in Burkina Faso and describes the epidemic situation. Section 3 presents data used for this analysis. Section 4 outlines the determinants of access to skilled maternal health care and provides descriptive statistics. Section 5 portrays the empirical method and presents the results. A detailed discussion of the results is provided in section 6 and section 7 concludes. 2. Challenges for the health care system in Burkina Faso Burkina Faso belongs is one of the poorest countries in the world. More than 80 percent of the population lives on less than $2 a day (UNDP 2005). The formal health care system is challenged by two major threats: high levels of maternal and child mortality and HIV/AIDS. Maternal and child mortality rates are among the highest in the world. The DHS from estimates the maternal mortality rate of 484 deaths per 100,000 live births and the infant mortality rate of 105 per 1,000 life births (INSD 2000). 1 In addition, Burkina Faso belongs to the countries in West Africa, which are more severe affected by the HIV/AIDS epidemic. Based on data provided by sentinel surveillance among women attending antenatal care clinics (ANC) and surveys conducted among sex workers, estimated adult HIV prevalence rate was 4.2 percent [range: ] by the end of 2003 (UNAIDS 2004). High levels of maternal and child mortality is associated with low access to maternal health care (Ronsmans et al. 2003). In Burkina Faso, more than 20 percent all pregnant women did not make any antenatal care visits during their last pregnancy, more than 40 percent of women did not receive any skilled antenatal care during last delivery 1 In the United States, about 5 infants in 1,000 births die (WHO 2005). 3

4 (INSD 2004). Furthermore, the quality of provided health care services is poor in Burkina Faso, since many health facilities lack staff and competence. The health facility survey conducted by Family Care International (2005) discovered major shortages of equipment, supplies, and essential drugs in the 20 considered health facilities in the Ouargaye district. 17 facilities had no electricity and 15 had no source of clean water. 5 health facilities did not employ any skilled birth attendants, most others were understaffed. The facility survey also revealed that most providers needed training in essential obstetric care functions. Prual et al. (2000) estimates the frequency of obstetric complications from medical interventions, omissions, and incorrect treatment in West Africa. 3 to 9 percent of pregnant women experienced severe maternal morbidity attributed to direct obstetric causes, further reflecting the poor quality of these services. The present paper argues that the poor quality of maternal health care services contributes also to the spread of HIV in Burkina Faso. HIV transmission in the health care sector is assumed to occur through unsafe injection practices with contaminated equipment. However, it is often argued, that unsafe injections are not sufficiently frequent (Schmid et al. 2004). Whether unsafe injection is a common practice in Burkina Faso is not entirely clear. Fitzner and colleagues (2004) observed 116 injections in 52 health facilities. They reported that almost all injections were given with new and singleuse syringes and needles. In contrast to this finding, the AFRO Logistics Project assessment on injection safety reported that only 11 percent of rural health centers, 60 percent of provincial dispensaries, and 80 percent of urban health centers used new syringes and needles for each injection. A substantial amount of injections were given by untrained laborers. In addition, 40 percent of urban health centers and 78 percent of rural health centers reported injection-associated abscesses among patients, which further indicates unsafe injection practices (Dicko et al. 2000). Altogether, the review of the available literature shows that access to the formal health sector is limited, while the overall quality of the services is poor. Evidences for unsafe injection practices are found guiding the question, if these injection practices contribute to the spread of HIV/AIDS in Burkina Faso. 4

5 3. Data Data is from the 2003 Demographic Health Survey (DHS) conducted in Burkina Faso. The DHS is a nationally representative survey, which was designed to provide information on fertility, family planning, antenatal-, delivery-, and postpartum-care, AIDS and other sexually transmitted infections. The survey was conducted by the National Statistical Office (Institut National de la Statistique et de la Démographie, INSD) and ORC Macro in collaboration with the Ministry of Health (Ministère de la Santé). DHS covered more than 9,000 households, where more than 12,000 women were interviewed. 2 In order to provide a more precise documentation of the current HIV epidemic in Burkina Faso, DHS carried out population-based tests to estimate HIV prevalence. In about one third of all households, DHS collected blood from eligible women and men who voluntarily consented for HIV testing. Participation rates for HIV testing were high percent (85.2 percent) of eligible women (men) consented for HIV testing, 4.4 percent (6.6 percent) of women (men) refused to be tested, and 1.9 percent (4.8) percent were absent from the household and could not be tested. Estimates based on DHS data suggests that HIV prevalence is 1.8 (1.9) percent for women (men). Unlike in other countries, where HIV prevalence rates are higher for women than for men, prevalence rates for men and women do not statistically differ (Pearson Chi2 = ). Of note, the population-based estimate is substantially lower than those provided by UNAIDS (2004). However, since UNAIDS estimates are based on sentinel site surveillance, targeting high-risk populations and women attending antenatal care clinics, population-based estimates provide a more accurate estimate of the true HIV prevalence. The paper at hand analyzes DHS data for a sub-sample of women who gave birth in the past 5 years (N = 7,367). Information is available for antenatal care at last pregnancy. HIV serostatus is available for 2,448 women (details on the characteristics of the considered sub-sample can be found in Appendix 1). HIV prevalence is lower in the 2 A detailed description can be found in INSD (2004). 5

6 considered sub-sample (1.8 percent compare to 2.2 percent in the group of women who did not give birth in the past 5 years). However, the difference is statistically not significant. Table 1: HIV prevalence rates by selected background characteristics (in percent) Total 1.84 Education: None 1.60 Education: Primary 3.38 Education: Secondary 3.61 * Wealth: Poorest 1.21 Wealth: Poorer 1.47 Wealth: Middle 1.23 Wealth: Richer 1.85 Wealth: Richest 3.93 ** Residence: Urban 4.38 Residence: Rural 1.36 *** Note: Significance levels are based on the Pearson test of independence: *** 1%, ** 5%, and * 10% significance level Table 1 provides HIV prevalence rates for women who gave birth in the past 5 years by selected background characteristics. Usually poor health is associated with poverty (Feinstein 1993). However, this is not the case for HIV/AIDS, since HIV prevalence rates significantly increase with socio-economic status such as wealth and education. HIV prevalence in the group of women who received secondary education is more than double of those who did not receive any formal education. 3 The same pattern can be found for household-wealth. This finding is consistent with other studies in Sub Saharan Africa (Wojcicki 2005). People with higher socio-economic status are typically more likely to live in urban areas, where HIV prevalence is per se higher. Thus, the relationship between wealth and HIV prevalence could be due to urban residence (Shelton et al. 2005). However, it is also possible that people with higher socio-economic 3 Only 5 women in the sub-sample received higher education, none of these women was HIV positive. These women are not included for the Pearson test of independence. 6

7 status are at higher risk due to their sexual behavior (Philipson and Posner 1995) or due to better access to the formal health care system (Gisselquist et al. 2003). 4. Maternity care and the risk of HIV infection According to WHO definition, doctors, nurses and midwifes are considered as skilled attendants, excluding trained and untrained traditional birth attendants (WHO 1996). Access to skilled maternity care is still limited in Burkina Faso. 26 percent of women in the sub-sample did not receive prenatal care by skilled health personnel during last pregnancy, only 2.6 percent of women received prenatal care by a doctor. An important aspect of prenatal care is the administration of tetanus toxoid injections given to mothers during pregnancy to protect children from neonatal tetanus, a frequent cause of infant death in many developing countries. These injections are typically given in the upper arm or midthigh, either into a muscle or under the skin. About 70 percent of women in the sub-sample received the vaccination during last pregnancy. Access to skilled birth assistance during last pregnancy is also low. 60 percent of women in the considered sub-sample gave their last birth without a skilled birth attendant. Table 2 provides information about access to skilled maternity health care by selected background characteristics. Since the structural reform of Burkina Faso s health care sector, the usage of primary health care imposes user fees. Thus, women with higher socio-economic status, measured by education attainment and household wealth, are more likely to receive skilled antenatal and delivery care. Furthermore, the data shows that women who consider the distance to the next health care facility as a big problem are less likely to receive any skilled maternity health care. Since antenatal health care services are more likely to be located in urban settings, women living in urban areas are more likely to receive skilled maternity care. One could argue that discrimination of unmarried women leads to lower provision of maternity health care services for women who have never been married or are not living together with their partner. This pattern cannot be found in the considered subsample. However, women who have never been married are more likely to be younger. 7

8 Young women are more likely to be pregnant for the first time, which could increase the likelihood to receive skilled maternity health care services. Table 2: Maternal health care by selected background characteristics Skilled Skilled prenatal birth care assistance Education: None Education: Primary Education: Secondary 1.00 *** 0.93 *** Wealth: Poorest Wealth: Poorer Wealth: Middle Wealth: Richer Wealth: Richest 0.96 *** 0.83 *** Marital: Never married Marital: Married Marital: Living together Marital: Widowed Marital: Not living together 0.77 ** 0.59 *** Distance: Big problem Distance: Small problem 0.81 *** 0.53 *** Residence: Urban Residence: Rural 0.70 *** 0.33 *** Note: Significance levels are based on the Pearson test of independence: *** 1%, ** 5%, and * 10% significance level Table 3 presents HIV prevalence rate by the use of maternal health care services. It shows that women who were in contact with the maternity health care system have systematically higher HIV risk. HIV prevalence doubles if women received skilled prenatal care. The same pattern can be found for women who had access to skilled birth attendance, but the difference to women who did not have access to skilled birth assistance, is not significant. HIV prevalence is lowest for women who reported no antenatal visits but prevalence rates do not continuously increase with number of antenatal care visits. HIV prevalence is highest for women who reported one and three visits. HIV prevalence is 8

9 lowest, when delivery occurred at home and increases dramatically, when the delivery took place in a private health facility. However, only a minority of women delivered in private facilities. Most importantly, the univariate analysis shows that HIV prevalence significantly increases with the number of tetanus injections suggesting that HIV risk could be associated with unsafe injection practices. Table 3: HIV prevalence rate by use of maternal health care services HIV Freq. + Tetanus injections: Tetanus injections: Tetanus injections: Tetanus injections: *** Skilled prenatal care: no Skilled prenatal care: yes * Skilled prenatal care: Doctor Skilled prenatal care: Nurse Skilled prenatal care: Both No of antenatal care visits: No of antenatal care visits: No of antenatal care visits: No of antenatal care visits: No of antenatal care visits: ** Skilled birth attendant: no Skilled birth attendant: yes Skilled birth attendant: Doctor Skilled birth attendant: Nurse Skilled birth attendant: Both Place of delivery: Home Place of delivery: Public Place of delivery: Private *** Note: Significance levels are based on the Pearson test of independence: *** 1%, ** 5%, and * 10% significance level 9

10 5. Multivariate specification The unconditional pattern of the data provided in the previous section suggests a positive dependence between exposure to the maternity health care system and the risk of HIV infection. To test if this dependency holds up when alternative transmission modes (i.e. sexual transmission) are considered, the conditional probability of HIV infection is estimated by using a multivariate Logit model. The corresponding coefficients can be found in Table 4 (column 1). One could argue that reverse causality hampers the interpretation of the regression results. The positive relation between HIV status and exposure to maternity health care could be explained by HIV-positive women being more likely to receive maternal health care. This could be the case if antiretroviral treatment is available to reduce HIV transmission from mother to child, which increases the incentive to search for prenatal health care. Another possibility is that HIV-positive women are more likely to be sick and thus, search for treatment (Schmid et al. 2004). Once in contact with the health care system the probability to access maternal health care services increases. If this holds to be true, tetanus injections should be correlated with factors indicating alternative transmission modes. Appendix 2 shows that women who received antenatal care and tetanus toxoid injections do not reported higher number of sexual partners than women who did not receive maternal health care. However, this empirical evidence does not fully prove, that reverse causality is irrelevant since it is thinkable that having received maternal health care is correlated with other factors, which increase the risk of HIV transmission (such as special sexual practices or the type of sexual networks). Since this information is not available, the present paper uses the two-stage residual inclusion method (2SRI) to account for endogenous regressors. The 2SRI approach generates consistent estimators if outcome and auxiliary equations are non-linear (Terza 2005). It considers endogenous regressors as an omitted variable problem, where unobserved characteristics influence both, the endogenous variable (probability of HIV infection) and the exogenous variable (number of tetanus injections). In the first stage, the 2SRI estimates the number of tetanus injections (Poisson model). The regressors (instruments) for the first-stage reduced form regression are 10

11 socioeconomic variables measuring the spending capacity (wealth, education) and a dummy variable indicating if the distance to the next health facility is considered as a problem. These instruments serve as proxies for access barriers, which influence HIV status only over their impact on accessing maternal health care services but have no direct impact on HIV status. The corresponding regression coefficients for the first-stage regression can be found in Appendix 3. The residuals of the first stage equations include all unobserved characteristics, which jointly influence the risk of HIV infection and the likelihood to receive maternal health care. Therefore, the outcome regression for the probability of HIV infection (Logit model) is estimated including the first-stage residuals as additional regressors. The corresponding regression coefficients of the second-stage regressions can be found in Table 4 (column 2). To account for sexual transmission, the model includes the number of sexual partners in the previous 12 month, which ranges from zero to two partners. It is evident, that the risk of sexual transmission is accumulated over all sexual partners, but the number of lifetime partners is not available. Therefore, the regressions control for age, assuming that the number of life-time partners increases with age. Furthermore, the risk of HIV infection depends on HIV prevalence in the contact group (sexual contacts, contacts with contaminated blood). Risk profiles of the contact groups are not available and thus, regional HIV prevalence rates are used as a proxy (regional HIV prevalence rates are presented in Appendix 4). The results from the Logit model confirm the findings from the univariate analysis. Receiving tetanus injections is associated with increasing risk of HIV infection. When controlling for endogeneity, the regression coefficient for number of tetanus toxoid injection becomes much larger. The coefficient is less precisely estimated, but still significant on the 10 percent level. In contrast to the previous hypothesis, that HIV positive women are more likely to be in contact with the official health care sector and thus, are more likely to receive tetanus injections, the result suggests that HIV positive women are be less likely receive tetanus injections. 4 4 A similar result is achieved when using a linear regression model with instrumental variables. Results are not reported but are available from the author. 11

12 Table 4: Regression results (dependent variable: HIV serostatus) coef. z coef. z Skilled prenatal care No of tetanus injections 0.23 *** * 1.89 No of partners: No of partners: *** ** 2.48 Agegroup: Agegroup: Agegroup: Agegroup: Agegroup: Agegroup: HIV prevalence 0.44 *** *** 2.59 Residuals _cons *** *** Logit Note: *** 1%, ** 5%, * 10% significance levels. 2SRI 6. Discussion The study provides evidence for the importance of unsafe maternal health care on the transmission of HIV in Burkina Faso. Tetanus toxoid injections are positively associated with increased HIV risk. Since several studies provide evidence for a correlation between injections and HIV seropositivity (Quigley et al. 1997, 2000; Bloom et al. 2002), unsafe injection practices in maternal health care and other primary health care settings may contributes to the spread of HIV in other African countries as well. In this light, the results of the study conducted in Rakai, Uganda (Gray et al. 2005) may need to be reinterpreted. Gray and colleagues report a significant increase in the risk of HIV acquisition during pregnancy, which is unlikely to be due to sexual behaviors. They conclude that the difference might be attributable to hormonal changes during pregnancy. However, since this study does not control for the exposure to the health care system, recent pregnancy could be also proxy for receiving unsafe maternal health care. Detailed empirical models, which consider sexual transmission and transmission by contaminated 12

13 injection syringes, can help to separate the impact of biological factors from the impact of unsafe medical care. Additionally, the result of the 2SRI model suggests that women who are HIV positive are less likely to receive tetanus injections. The phenomenon may be explained by rational behavior on the supply and the demand side of health care. If the maternal health care provider knows (or at least guesses) the serostatus of the patient, 5 the provider may be less willing to administer injections. This behavior is rational if the provider fears to get infected by an accidental needle stick injury, or if new syringes and needles are not available and the provider does not want to contaminate scarce equipment. Viewed from the demand side, women who adopt a healthier life style may be also more likely to vaccinate their children. The present paper cannot not quantify if the supply or the demand of health care is responsible for this phenomenon and further research on this issue is needed. However, the results indicate that studies analyzing the effect of injections on HIV risk, which do not control for reverse causality, run into the risk to underestimate the impact of injections on the spread of HIV. Nationwide estimates for HIV prevalence rates are often based on surveys for women attending antenatal care clinics (ANC). Typically, ANC estimates exceed prevalence rates generated from general population surveys. Since women receiving maternal health care have systematic higher risk to acquire HIV infection, ANC estimates systematically overestimate the real prevalence in a population. Thus, to create an effective surveillance system, regularly conducted general population surveys can provide a more accurate estimate of the true HIV prevalence. Several factors hamper the interpretation of the results presented in the paper at hand. DHS data relies on self-reported sexual behavior and it is not known if results are skewed by miss-reporting, in particular under-reporting the number of partners. Furthermore, number of partners refers to the previous 12 month. To estimate the impact of sexual behavior on HIV prevalence, number of lifetime partner could deliver more accurate results. Unfortunately, data on number of lifetime partners is not available. 5 This is not unlikely if a patient has symptoms related to a HIV infection. Furthermore, to monitor the spread of HIV, many antenatal health care facilities conduct HIV tests on pregnant women. 13

14 Furthermore, the analysis does not control for sexual practices. The risk of HIV transmission by penile-vaginal intercourse is low and other sexual practices such as anal intercourse is by far more risky (Royce et al. 1997). However, DHS does not provide information on sexual practices other than condom use, which is available for the last sexual episode only. 6 Therefore, it is not possible to quantify the relative importance of sexual transmission versus transmission by unsafe medical care. 7. Conclusion The present paper shows that receiving maternal health care significantly increases the risk of HIV infection in Burkina Faso. This finding is most likely explained by unsafe injection practices (reuse of syringes) since tetanus toxoid injections are positively associated with increased HIV risk. The results indicate that unsatisfactory quality of maternal health care contributes to the spread of HIV in Burkina Faso. There is an urgent need to improve the quality of maternal health care services. Distributing low-quality services widely can further accelerate the spread of HIV in Burkina Faso (and in other sub-saharan countries). Therefore, public health interventions should concentrate on the provision of sterile medical equipment (such as surgical instruments and syringes) and on training for health workers to adequately use them. Since HIV-positive mothers carry also high risk of HIV transmission to their children, these interventions can be highly effective to reduce the spread of HIV/AIDS. In addition, patients should be widely informed about the risk of HIV transmission by contaminated injections. Informed patients can take protective action for themselves when seeking medical care, for instance by insisting on unused injection equipment or using own equipment. Due to lack of relevant data, this study cannot quantify the relative importance of sexual transmission versus transmission by unsafe health care. However, since knowledge on the relevance of different transmission mode is essential for efficiently design public 6 Condom use during last sex is not included as regressor, since condom use and number of partner are strongly correlated. More than 60 percent of women who reported two sex partners in the previous 12 month used condoms during last sexual intercourse. 14

15 health interventions aimed to reduce the spread of HIV in Sub Saharan Africa, further research on this issue is necessary. 15

16 Appendix 1: Characteristics of the sub-sample Gave birth Tested for in past 5 HIV years Total Education: None Education: Primary Education: Secondary Education: Higher 0.36 *** 0.33 * Wealth: Poorest Wealth: Poorer Wealth: Middle Wealth: Richer Wealth: Richest 0.43 *** 0.31 *** Marital: Never married Marital: Married Marital: Living together Marital: Widowed Marital: Divorced Marital: Not living together 0.55 *** 0.26 Religion: Catholic Religion: Protestant Religion: Muslim Religion: Traditional/animist Religion: No religion 0.57 *** 0.28 * Distance: big problem Distance: small problem 0.57 *** 0.34 Residence: Urban Residence: Rural 0.64 *** 0.34 *** Age: Age: Age: Age: Age: Age: Age: *** 0.31 Note: Significance levels are based on the Pearson test of independence: *** 1%, ** 5%, and * 10% significance level 16

17 Appendix 2: Cross-table number of partners and maternal health care Number of partners: Chi2 Prenatal care: no Prenatal care: yes Tetanus injection: no Tetanus injection: yes Note: Chi2 values are based on the Pearson test of independence Appendix 3: First-stage regression results coef Wealth: Poorer Wealth: Middle 0.13 ** 2.15 Wealth: Richer 0.20 *** 3.10 Wealth: Richest 0.33 *** 4.91 Education: Primary 0.16 *** 2.64 Education: Secondary Education: Higher Distance: small problem 0.09 ** 2.26 _cons Dependent variable Tetanus inject. Model Poisson Note: *** 1%, ** 5%, and * 10% significance level z 17

18 Appendix 4: Regional HIV prevalence rates Ouagadougou 4.63 Boucle de Mouhoun 2.01 Centre (sans Ouagadougou) 1.00 Centre-Sud 0.95 Plateau Central 1.04 Centre-Est 1.37 Centre-Nord 1.06 Centre-Ouest 2.70 Est 1.44 Nord 1.32 Cascades 2.89 Hauts Basins 2.68 Sahel 0.20 Sud-Ouest 3.33 Note: Estimates for regional prevalence rates are bases on full sample of men and women. Estimates are un-weighted. 18

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