Geospatial analysis of household spread of Ebola virus in a quarantined village - Sierra Leone, 2014.

We performed a spatial-temporal analysis to assess household risk factors for Ebola virus disease (Ebola) in a remote, severely-affected village. We defined a household as a family's shared living space and a case-household as a household with at least one resident who became a suspect, probable, or confirmed Ebola case from 1 August 2014 to 10 October 2014. We used Geographic Information System (GIS) software to calculate inter-household distances, performed space-time cluster analyses, and developed Generalized Estimating Equations (GEE). Village X consisted of 64 households; 42% of households became case-households over the observation period. Two significant space-time clusters occurred among households in the village; temporal effects outweighed spatial effects. GEE demonstrated that the odds of becoming a case-household increased by 4·0% for each additional person per household (P < 0·02) and 2·6% per day (P < 0·07). An increasing number of persons per household, and to a lesser extent, the passage of time after onset of the outbreak were risk factors for household Ebola acquisition, emphasizing the importance of prompt public health interventions that prioritize the most populated households. Using GIS with GEE can reveal complex spatial-temporal risk factors, which can inform prioritization of response activities in future outbreaks.

Is Zimbabwe ready to transition from anonymous unlinked sero-surveillance to using prevention of mother to child transmission of HIV (PMTCT) program data for HIV surveillance?: results of PMTCT utility study, 2012.

BACKGROUND: Prevention of mother-to-child transmission of HIV (PMTCT) programs collect socio-demographic and HIV testing information similar to that collected by unlinked anonymous testing sero-surveillance (UAT) in antenatal settings. Zimbabwe evaluated the utility of PMTCT data in replacing UAT. METHODS: A UAT dataset was created by capturing socio-demographic, testing practices from the woman's booking-card and testing remnant blood at a laboratory from 1 June to 30 September 2012. PMTCT data were collected retrospectively from ANC registers. UAT and PMTCT data were linked by bar-code labels that were temporarily affixed to the ANC register. A questionnaire was used to obtain facility-level data at 53 sites. RESULTS: Pooled HIV prevalence was 15.8 % (95 % CI 15.3-16.4) among 17,349 women sampled by UAT, and 16.3 % (95 % CI 15.8 %-16.9 %) among 17,150 women in PMTCT datasets for 53 sites. Pooled national percent-positive agreement (PPA) was 91.2 %, and percent-negative agreement (PNA) was 98.7 % for 16,782 women with matched UAT and PMTCT data. Based on UAT methods, overall median prevalence was 12.9 % (Range 4.0 %-19.4 %) among acceptors and refusers of HIV test in PMTCT compared to 12.5 % ((Range 3.4 %-19.5 %) among acceptors in ANC registers. There were variations in prevalence by site. CONCLUSION: Although, there is no statistical difference between pooled HIV prevalence in UAT compared to PMTCT program, the overall PPA of 91.2 % and PNA of 98.7 % fall below World Health Organisation (WHO) benchmarks of 97.6 % and 99.6 % respectively. Zimbabwe will need to strengthen quality assurance (QA) of rapid HIV testing and data collection practices. Sites with good performance should be prioritised for transitioning.

Routine HIV testing in the context of syndromic management of sexually transmitted infections: outcomes of the first phase of a training programme in Botswana.

OBJECTIVE: In 2004, the Ministry of Health adopted revised protocols for the syndromic management of sexually transmitted infections (STI) that included routine HIV testing. A training programme for providers was developed on the revised protocols that featured interactive case studies and training videos. An objective of the first phase of the training programme was to test its effect on four measures of clinical practice: (1) routine HIV testing; (2) performance of physical examination; (3) risk-reduction counselling and (4) patient education. METHODS: Clinical practice in a district where providers were trained was compared with a district without training. The measures of clinical practice were reported by 185 patients of providers who had been trained and compared with reports by 124 patients at comparison clinics. RESULTS: Relative to patients at comparison clinics, a higher percentage of patients of trainees reported that the provider: (1) offered an HIV test (87% versus 29%; p<0.001); (2) conducted a physical examination (98% versus 64%; p<0.001); (3) helped them to make a plan to avoid future STI acquisition (95% versus 76%; p<0.001) and (4) provided patient-specific information about HIV risk (65% versus 32%; p<0.001). Among patients offered HIV testing, the percentage who accepted did not differ between groups (38% of 161 patients of trainees versus 50% of 36 comparison patients; p = 0.260). Overall, 33% of patients of trainees and 14% of comparison patients were tested (p<0.001). CONCLUSION: A multifaceted training programme was associated with higher rates of HIV testing, physical examination, risk-reduction counselling and better HIV risk education.

Reported childhood tuberculosis treatment outcomes, Gaborone and Francistown, Botswana, 1998-2002.

SETTING: Botswana. OBJECTIVES: To estimate frequencies of tuberculosis (TB) treatment outcomes, assess the validity of reported treatment outcomes, and identify risk factors for death during TB treatment among children aged <15 years during 1998-2002. DESIGN: We examined TB treatment outcome frequencies using the national Electronic TB Registry (ETR) data. Treatment and medical records were reviewed to calculate predictive values (PV) for outcomes recorded in the ETR. We interviewed parents of children treated for TB and assessed risk factors for death during treatment via case-control study. RESULTS: Of 5483 patients, 3646 (67%) were cured or completed treatment and 577 (10.5%) died during treatment. The PV for ETR was 76% for death and 97% for cured or completed treatment. We interviewed parents of 91 children who died during treatment and 220 children who completed treatment. Human immunodeficiency virus (HIV) status was unknown for 76% of the children and 54% of the parents. Parent-reported adverse effects to anti-tuberculosis medication (adjusted odds ratio [aOR] 4.9, 95% confidence limit [CL] 2.2-9.2), and lower patient age (aOR 2.2, 95%CL 1.2-4.2) were associated with death during treatment. CONCLUSIONS: TB control programs in Botswana should assess for potential adverse effects of anti-tuberculosis medication and expand HIV testing among children with TB and their parents.

Baseline evaluation of routine HIV testing among tuberculosis patients in Botswana.

In January 2004, the government of Botswana introduced a policy of routine, non-compulsory human immunodeficiency virus (HIV) testing to increase testing and access to antiretroviral treatment (ART) for individuals presenting for medical treatment. Before a systematic implementation of the policy, we conducted a cross-sectional survey of tuberculosis (TB) record data from 46 clinics in 10 districts to assess baseline HIV testing rates among TB patients. Recorded HIV results from the facility TB register and TB treatment card were reviewed. Of the 1242 TB patients entered in the register, 47% had a recorded HIV result and 84% of these were co-infected with HIV. TB treatment cards were available for 862 (69%) registered patients. Among the 411 (47%) with test results recorded on the treatment card, 341 (83%) were HIV-infected; of these, 12% were reported to be receiving ART.

Explosive spread and effective control of human immunodeficiency virus in northernmost Thailand: the epidemic in Chiang Rai province, 1988-99.

The human immunodeficiency virus type 1 (HIV-1) epidemic began in Asia later than most in other regions but then spread very rapidly. Upper northern Thailand was severely affected, with among the highest infection rates in Asia. The first 12 years of the HIV epidemic in Chiang Rai, Thailand's northernmost province are described. HIV infection was not reported in Chiang Rai until 1988 but, within a few years more than half of the brothel-based female sex workers and one in six of 21-year-old male Royal Thai Army conscripts from the province were HIV infected. Infection rates in Chiang Rai have since declined following an aggressive prevention campaign, but the number of AIDS cases continues to mount, along with profound demographic, social and economic effects.

HIV-1 seroconversion in a prospective study of female sex workers in northern Thailand: continued high incidence among brothel-based women.

OBJECTIVES: To determine the incidence of HIV-1 infection, temporal trends in incidence, and risk factors for seroconversion in a cohort of female commercial sex workers (CSW) in upper northern Thailand, the region of Thailand with the highest rates of HIV-1 infection. METHODS: CSW were enrolled from 1991 through 1994 and evaluated prospectively with interviews, physical examination, testing for sexually transmitted diseases (STD), and serologic testing for HIV-1 infection. RESULTS: The incidence of HIV-1 seroconversion in the first year of follow-up was 20.3 per 100 person-years among 126 brothel-based CSW and 0.7 per 100 person-years among 159 other CSW who worked in other venues such as bars or massage parlors. Incidence remained elevated among brothel-based CSW who were enrolled later in the study compared with those who enrolled earlier. Through 1996, 30 women seroconverted. In a multivariable proportional hazards model, seroconversion was significantly associated (P < 0.05) with brothel-based sex work (adjusted risk ratio, 7.3) and Chlamydia trachomatis cervical infection (adjusted risk ratio, 3.3). CONCLUSION: Despite national HIV control efforts and declining rates of infection among young men in Thailand, brothel-based CSW may continue to be at high risk for HIV-1 infection. Additional efforts are needed to provide alternative economic choices for young women, to ensure universal condom use during commercial sex, and to develop new prevention technologies.

Mucosal disruption due to use of a widely-distributed commercial vaginal product: potential to facilitate HIV transmission.

OBJECTIVE: Policresulen vaginal suppositories are a condensation product of metacresolsulfonic acid and formaldehyde. We investigated their use by female commercial sex workers (CSW) and whether such use could facilitate HIV transmission. METHODS: We interviewed female CSW in Thailand about use of the product, and we directly observed the effects of self-administration of a single suppository by each of six women. RESULTS: Of 200 CSW interviewed, 32% had used policresulen vaginal suppositories in the preceding year and 46% had used them at some time. Many used them for reasons not listed on the package insert, such as improving their male partners' sexual pleasure, and most did not abstain from vaginal sex following use. Among 36 brothel-based and 67 non-brothel-based CSW with known HIV infection, the use of the product was not associated with HIV-1 infection (adjusted relative risk 1.0, 95% confidence interval, 0.5-2.0). Exfoliation of the vaginal and cervical mucosa was observed in all six CSW 1 day after product use, and, although it could have been the result of repeated examinations, an increase in genital HIV-1 RNA shedding was also detected in all three HIV-seropositive women. CONCLUSION: Although there was no epidemiological association with HIV infection, policresulen vaginal suppository use did disrupt the genital mucosa and therefore may have the potential to facilitate HIV transmission. Drug licensing authorities may wish to reassess the safety of this product. If the product continues to be distributed, steps should be taken to limit its use to the specific conditions for which it is indicated and to ensure that women abstain from vaginal sex following its use.

HIV-1 seroprevalence among childbearing women in northern Thailand: monitoring a rapidly evolving epidemic.

OBJECTIVES: To describe trends in prevalence of HIV-1 infection among women giving birth at Chiang Rai Hospital (CRH) and to assess risk factors associated with HIV infection in this population. DESIGN: Analysis of hospital registry data for all deliveries at CRH from 1990 to mid-1997. METHODS: From 1990 to mid-1997, women giving birth at CRH were tested for HIV-1 infection using enzyme immunoassay (EIA); positive sera were confirmed using a different manufacturer's EIA. Demographic and clinical data were abstracted from delivery-ward log books. RESULTS: Data from 40723 deliveries indicated that overall HIV-1 seroprevalence increased sharply, from 1.3% in 1990 to a peak of 6.4% in 1994, and then declined to 4.6% in the first 6 months of 1997. Prevalence was highest, at 7.0%, among young (age < or = 24 years) primigravidas, compared with 2.4% among older (age > or = 25 years) multigravidas. When we controlled for age, prevalence declined 40% from 1994 to 1997 among young primigravidas (95% confidence interval for percentage reduction, 16-57). Amongst older multigravid women, prevalence was consistently lower but increased steadily from 2.7% in 1994 to 3.4% in 1997. CONCLUSIONS: A rapid rise in HIV prevalence in childbearing women was followed by a sharp decline among young primigravidas. In each year, the prevalence was highest among young primigravidas. They may be the best subgroup of pregnant women for monitoring HIV epidemic trends, but they also represent a challenging prevention priority that will require its own targeted interventions.

Perspectives in fatal epidemics.

This article discusses four epidemics of fatal infectious diseases: a 1993 cluster of deaths among previously healthy persons in the southwestern United States that led to the identification of a new clinical syndrome, hantavirus pulmonary syndrome; the first epidemic of Ebola hemorrhagic fever identified in nearly two decades occurring in 1995 in Zaire, which resulted in 317 cases with a mortality rate of 77%; an outbreak of Legionnaires' disease among cruise ship passengers in 1994; and a 1989 cluster of illnesses among nonhuman primates in Reston, Virginia leading to the identification of a new strain of Ebola virus. In each outbreak, the public health emergency was recognized and reported by alert clinicians, and the control of disease was facilitated through rapid, coordinated responses involving multiple agencies. Such collaboration between clinical and public health entities and among various agencies will be increasingly needed as surveillance and diagnostic capabilities for emerging and reemerging infectious diseases are enhanced around the world.

The social ecology of syphilis.

Factors affecting the transmission of syphilis can be categorized into those acting at the level of individuals (e.g., number of sex partners) and others at the level of the sociophysical environment (e.g., availability of treatment services for curable infections). In a prior study, we identified several sociophysical factors correlated with the ten-year mean syphilis rate in a regression analysis of United States counties. In the present study we used qualitative methods to investigate additional aspects of some factors in the regression, as well as to identify entirely new factors. Twelve counties with populations less than 100,000 and ten-year mean syphilis rates that were greater or less than expected by the regression model were selected for a three to five day visit. The case study protocol included observations, unstructured interviews with care providers and county residents, and a standardized questionnaire completed by state and local sexually transmitted disease control personnel pertaining to characteristics and practices of the local health department. Comparisons of the field notes and questionnaires revealed patterns of factors of the sociophysical environment that potentially affect county syphilis rates. These included access to the health department STD clinic, race relations, employment opportunities for minorities, interagency coordination, STD outreach activities, the social acceptability of discussing STDs, and intercommunity dynamics. In addition we noted the disproportionate influence of particular individuals on these factors. Some of the factors identified are readily quantifiable and could enhance the predictive power of multivariable models of county syphilis rates. The hypotheses generated by this study may also lead to a better measurement and understanding of potentially important environmental determinants of community syphilis rates, and the development of new or enhanced prevention strategies.

Tuberculosis in asymptomatic HIV-infected adults with abnormal chest radiographs screened for tuberculosis prevention.

BACKGROUND: Isoniazid preventive therapy (IPT) prevents tuberculosis (TB) in people living with HIV (human immunodeficiency virus, PLWH). Symptom screening without chest radiographs (CXRs) was established as the strategy for excluding TB disease among PLWH seeking IPT in Botswana's 2001 pilot project. This strategy was evaluated in 2004-2006 among candidates screened for an IPT clinical trial. METHODS: PLWH referred from clinics and HIV testing centers were screened for TB symptoms. All asymptomatic candidates received CXRs; those with abnormal CXRs were investigated further. RESULTS: Among 2732 asymptomatic candidates screened, 302 (11%) had abnormal CXRs potentially compatible with TB; TB disease was diagnosed in 43 of these 302 (14%), or 43 (1.6%) of the 2732 asymptomatic candidates. While not associated with CD4 lymphocyte counts < 200 cells/mm(3), TB was associated with a positive tuberculin skin test (relative risk 2.1, 95%CI 1.1-4.0). IPT was initiated in 113 (62%) of 182 asymptomatic PLWH with abnormal CXRs; 8/113 (7%) subsequently developed TB, and 7/8 (88%) successfully completed anti-tuberculosis treatment. CONCLUSIONS: The prevalences of abnormal CXRs and TB were respectively 2.6- and 8.9-fold higher among asymptomatic PLWH screened for the trial than in the pilot. A cost-effectiveness analysis is needed to determine whether the benefits of symptom screening alone are offset by the risk of inducing INH resistance by excluding CXRs during screening.

Declining syphilis prevalence among pregnant women in northern Botswana: an encouraging sign for the HIV epidemic?

OBJECTIVES: To evaluate trends in syphilis prevalence among antenatal women in a high HIV prevalence setting in northern Botswana. METHODS: Laboratory logbooks of antenatal syphilis testing for 1992-2003 in Francistown, Botswana's second largest city, were reviewed, and a consecutive sample of 750 women per year from 1992-2003 were analysed. VDRL result and age were recorded. A positive result was considered a case. RESULTS: Overall syphilis prevalence (VDRL positive) among pregnant women in Francistown decreased from 12.4% in 1992 to 4.3% in 2003 (p< or =0.001). The downward trend in overall syphilis prevalence began in 1997. There was no change in syphilis prevalence from 1992-6. Beginning in 1997, there has been a significant decrease in syphilis prevalence in all age groups. CONCLUSIONS: Syphilis in pregnant women in Francistown has been decreasing for the last 6 years, despite extremely high HIV prevalence (stable at > or =40% since 1996) in the same population. Reasons contributing to the decline in syphilis rates may include nationwide implementation of syndromic management of sexually transmitted diseases (STDs) in 1992, improved access to health care, and less risky sexual behaviour. There is evidence from other sources indicating that risky sexual behaviour in Botswana has decreased during the HIV epidemic.

Living with HIV. Experiences and perspectives of HIV-infected sexually transmitted disease clinic patients after posttest counseling.

OBJECTIVES: To determine whether human immunodeficiency virus (HIV)-infected STD clinic patients receive needed services and to determine the social consequences of testing HIV-positive. STUDY DESIGN: Sexually transmitted disease clinic patients in Baltimore, Miami, and Newark who had first been told about a positive HIV test 6 to 24 months previously were recontacted and interviewed. RESULTS: Out of 416 persons we attempted to contact, we interviewed 142 who had first learned that they were HIV-infected 6 to 24 months previously. Most interviewees were male (57%), black (82%), and heterosexual and had a low socioeconomic status. Twenty-five percent said they had never received medical care for their HIV infection. Most of those not in care said they were never referred, were "in denial," or did not want medical care. Interviewees had disclosed their status selectively; but "because of HIV," 4% had lost a job, 1% had been asked to move by a landlord, and 1% had been assaulted. Seventy-six percent would recommend that others take an HIV test; 11% would not recommend it. CONCLUSIONS: Most patients interviewed were getting medical care and, despite some negative consequences, most would recommend HIV testing to others. To identify and address local barriers to needed services, we suggest that clinic staff routinely recontact consenting HIV-infected patients after posttest counseling.

Prevalence of lead intoxication in urban, adult medical inpatients.

Medical inpatients in inner-city hospitals have both potentially lead-related disorders and potential lead exposure. To see whether there is substantial unexpected lead intoxication in this population, we did a cross-sectional study of 117 consecutively admitted patients to a general medical ward of an inner-city university hospital. The mean (SD) blood lead level was 6.7 (2.8) micrograms/dL, with a range of 0 to 37 micrograms/dL. Twenty-one patients (18%) had mildly elevated lead levels (10 to 19 micrograms/dL) and 2 patients (2%) had moderately elevated lead levels (20 to 44 micrograms/dL). Only 1 of 117 patients (0.9%, 95% CI: 0.0% to 2.6%) had lead intoxication (a lead level > or = 20 micrograms/dL or a lead level > or = 15 micrograms/dL and a free erythrocyte protoporphyrin level > 90 micrograms/dL of erythrocytes, with no alternative explanation for the laboratory abnormalities). We conclude that lead intoxication is uncommon in this population and that routine screening is not warranted. Although mild elevation of blood lead level is common, the clinical significance remains to be determined.

Medication use by female sex workers for treatment and prevention of sexually transmitted diseases, Chiang Rai, Thailand.

BACKGROUND: Female sex workers (FSWs) in Thailand are at high risk for sexually transmitted diseases (STDs). Although regular attendance at public STD clinics is required, FSWs may frequently use medications obtained in the community for STDs. OBJECTIVES: To determine the frequency of use of medications for STDs from sources other than public STD clinics among FSWs in Thailand and to describe factors associated with such medication use. METHODS: A cross-sectional survey of FSWs attending the public STD clinic in Chiang Rai, Thailand, was performed. RESULTS: Of the 200 FSWs interviewed, 55% had ever used medications to treat or prevent STDs from a source other than a public STD Clinic, and 36% had done so in the prior year. Most use (79%) was to treat STD symptoms, and medication was most frequently obtained directly from a pharmacy (54%). This use of community medication for STDs was associated with younger age, non-Thai ethnicity, seeking STD treatment during the current clinic visit, and brothel-based sex work. CONCLUSIONS: Use of medications from various sources in the community was common among these FSWs. Further research is needed to determine the appropriateness of this treatment. Innovative methods to ensure adequate quality STD care by community providers and to improve the health-care-seeking behaviors of these high-risk women are needed.

PIP: The frequency of use of medications obtained from sources other than medical clinics (e.g., pharmacy, friends) for the treatment of sexually transmitted diseases (STDs) was investigated in a cross-sectional survey of 200 female commercial sex workers attending the public STD clinic in Chiang Rai, Thailand, in 1995. Only 6% of respondents were seeking STD treatment during the index clinic visit; the majority were making government-mandated visits. Overall, 55% of women reported ever-use of a medication obtained in the community to treat or prevent STDs and 36% had done so in the year preceding the study. In 79% of cases, the medication was used to treat STD symptoms. Medication was obtained directly from a pharmacy in 54% of cases. Other sources included a private doctor (30%), the hospital (6%), a health care worker at the commercial sex work establishment (2%), or a friend or coworker (2%). Women could not identify 123 (87%) of the 141 medications reported. The use of community medicines for STDs was significantly associated with younger age, non-Thai ethnicity, seeking STD treatment during the index clinic visit, and brothel-based sex work. Attention should be given to innovative methods to ensure adequate quality STD care by community providers and to improve the health care-seeking behaviors of high-risk Thai women.

Seroprevalence of HIV among female sex workers in Bangkok: evidence of ongoing infection risk after the "100% condom program" was implemented.

BACKGROUND: After implementation in 1991 of a nationwide campaign to promote condom use during commercial sex, HIV-1 seroprevalence among young men began to decrease in 1994. However, it is unknown to what degree female sex workers (FSWs) have been protected from infection. METHODS: FSWs attending a government clinic in Bangkok in 1997 and 1998 were interviewed, counseled, and tested for evidence of prior syphilis by Treponema pallidum hemagglutination assay (TPHA) and for HIV-1 antibodies. RESULTS: Among the 500 participants, women who began sex work more recently reported less risky sex behavior when they were first potentially exposed to HIV infection, and TPHA reactivity rates were lower among these women. However, their HIV infection rates were higher. HIV seroprevalence was 5.5% among 91 women who began sex work before 1989, 8.0% among 87 women who began during 1990 to 1993, and 12.5% among 322 women who had begun since 1994. CONCLUSIONS: Although condom use is critical to HIV prevention, women in this study who began sex work after the condom promotion campaign was implemented were still at high risk for HIV infection. Additional measures are needed to prevent HIV infection among the many young women who initiate or continue to engage in commercial sex.

Typing of Chlamydia trachomatis strains from urine samples by amplification and sequencing the major outer membrane protein gene (omp1).

OBJECTIVES: To develop a novel protocol for the extraction, amplification, and sequencing of Chlamydia trachomatis MOMP gene (omp1) from urine, a non-invasive source, and apply it to an epidemiological study on the distribution of C trachomatis strains in a population of pregnant women in Thailand. METHODS: The C trachomatis DNA was extracted from culture stocks and urine using a slightly modified commercially available kit, the High Pure PCR Template Preparation Kit (Roche Molecular Biochemicals, IN, USA). The PCR and sequencing primers used for the amplification and sequencing of the omp1 were designed based on the nucleotide sequence of multiple C trachomatis strains found in GenBank. The protocol for the extraction, amplification, and sequencing was tested on laboratory culture stocks of reference strains of all C trachomatis serovars and on urine samples collected in a cross sectional study designed to assess the prevalence of C trachomatis infections in the cities of Bangkok and Chiang Rai, Thailand. RESULTS: The omp1 gene was successfully amplified and sequenced from 18 laboratory C trachomatis reference strains and from 45 C trachomatis positive urine clinical samples collected from asymptomatic pregnant women. Among clinical samples, we found nine different C trachomatis genotypes: F (11, 25%), D (10, 22.6%), H (5, 11.7%), K (5, 11.7%), E (4, 9.3%), Ia (3, 7%), B (3, 7%), Ja (2, 4.5%), and G (1, 2.3%). One specimen generated an omp1 DNA sequence pattern indicating the presence of a mixed infection with at least two different serovars. CONCLUSIONS: Urine is a convenient and reliable source for genotyping C trachomatis strains. A clear advantage of urine over traditional samples, such as cervical swabs, is that urine is a non-invasive source which makes collection easier and thus facilitates the enrolment of patients in clinical and epidemiological studies. In addition to typing, urine is increasingly used for diagnosis of C trachomatis infection by several commercially available nucleic acid amplification assays which represents a distinct advantage for collecting, transport, storage, and laboratory handling of samples.