Immunity to poliovirus in Afghanistan: A household sampling method for serological assessment based on geographical information systems.

Afghanistan continues to experience challenges affecting polio eradication. Mass polio vaccination campaigns, which aim to protect children under the age of 5, are a key eradication strategy. To date, the polio program in Afghanistan has only employed facility-based seroprevalence surveys, which can be subject to sampling bias. We describe the feasibility in implementing a cross-sectional household poliovirus seroprevalence survey based on geographical information systems (GIS) in three districts. Digital maps with randomly selected predetermined starting points were provided to teams, with a total target of 1,632 households. Teams were instructed to navigate to predetermined starting points and enrol the closest household within 60 m. To assess effectiveness of these methods, we calculated percentages for total households enrolled with valid geocoordinates collected within the designated boundary, and whether the Euclidean distance of households were within 60 m of a predetermined starting point. A normalized difference vegetation index (NDVI) image ratio was conducted to further investigate variability in team performances. The study enrolled a total of 78% of the target sample with 52% of all households within 60 m of a pre-selected point and 79% within the designated cluster boundary. Success varied considerably between the four target areas ranging from 42% enrolment of the target sample in one place to 90% enrolment of the target sample in another. Interviews with the field teams revealed that differences in security status and amount of non-residential land cover were key barriers to higher enrolment rates. Our findings indicate household poliovirus seroprevalence surveys using GIS-based sampling can be effectively implemented in polio endemic countries to capture representative samples. We also proposed ways to achieve higher success rates if these methods are to be used in the future, particularly in areas with concerns of insecurity or spatially dispersed residential units.

Use, Acceptability, Performance, and Health Impact of Hollow Fiber Ultrafilters for Water Treatment in Rural Kenyan Households, 2009-2011.

Diarrheal illness remains a leading cause of morbidity and mortality in children < 5 years in developing countries, and contaminated water contributes to diarrhea risk. To address this problem, a novel hollow fiber ultrafilter (HFU) was developed for household water treatment. To test its impact on water quality and infant health, we conducted a cluster-randomized longitudinal evaluation in 10 intervention and 10 comparison villages in Kenya, attempting to enroll all households with infants (< 12 months old). We conducted a baseline survey, distributed HFUs to intervention households, made biweekly home visits for 1 year to assess water treatment practices and diarrhea in infants, and tested water samples from both groups every 2 months for Escherichia coli. We enrolled 92 infants from intervention households and 74 from comparison households. During the 1-year study period, 45.7% of intervention households and 97.3% of comparison households had at least one stored water sample test positive for E. coli. Compared with comparison households, the odds of E. coli contamination in stored water was lower for intervention households (odds ratio [OR]: 0.42, 95% CI: 0.24, 0.74), but there was no difference in the odds of reported diarrhea in infants, adjusting for covariates (OR: 1.19, 95% CI: 0.74, 1.90). Although nearly all water samples obtained from unprotected sources and filtered by the HFU were free of E. coli contamination, HFUs alone were not effective at reducing diarrhea in infants.

Evaluation of an Emergency Bulk Chlorination Project Targeting Drinking Water Vendors in Cholera-Affected Wards of Dar es Salaam and Morogoro, Tanzania.

In August 2015, an outbreak of cholera was reported in Tanzania. In cholera-affected areas of urban Dar es Salaam and Morogoro, many households obtained drinking water from vendors, who sold water from tanks ranging in volume from 1,000 to 20,000 L. Water supplied by vendors was not adequately chlorinated. The Tanzanian Ministry of Health, Community Development, Gender, Elderly and Children and the U.N. Children's Fund, Tanzania, collaborated to enroll and train vendors to treat their water with 8.68-g sodium dichloroisocyanurate tablets (Medentech, Ireland). The Centers for Disease Control and Prevention (CDC) provided monitoring and evaluation support. Vendors were provided a 3-month supply of chlorine tablets. A baseline assessment and routine monitoring were conducted by ward environmental health officers. Approximately 3 months after chlorine tablet distribution, an evaluation of the program was conducted. The evaluation included a full enumeration of all vendors, an in-depth survey with half of the vendors enumerated, and focus group discussions. In total, 797 (88.9%) vendors were included in the full enumeration and 392 in the in-depth survey. Free residual chlorine (FRC) was detected in 12.0% of tanks at baseline and 69.6% of tanks during the evaluation; however, only 17.4% of these tanks had FRC ≥ 0.5 mg/L. The results suggest high acceptability and use of the chlorine tablets by water vendors. However, given variation in the water source used and longer storage times, dosing could be increased in future programming. Bulk chlorination using chlorine tablets offers an efficient community-level approach to treating water closer to the point of use.

Impact of the Integration of Water Treatment, Hygiene, Nutrition, and Clean Delivery Interventions on Maternal Health Service Use.

AbstractReducing barriers associated with maternal health service use, household water treatment, and improved hygiene is important for maternal and neonatal health outcomes. We surveyed a sample of 201 pregnant women who participated in a clinic-based intervention in Kenya to increase maternal health service use and improve household hygiene and nutrition through the distribution of water treatment products, soap, protein-fortified flour, and clean delivery kits. From multivariable logistic regression analyses, the adjusted odds of ≥ 4 antenatal care (ANC4+) visits (odds ratio [OR] = 3.0, 95% confidence interval [CI] = 1.9-4.5), health facility delivery (OR = 5.3, 95% CI = 3.4-8.3), and any postnatal care visit (OR = 2.8, 95% CI = 1.9-4.2) were higher at follow-up than at baseline, adjusting for demographic factors. Women who completed primary school had higher odds of ANC4+ visits (OR = 1.8, 95% CI = 1.1-2.9) and health facility delivery (OR = 4.2, 95% CI = 2.5-7.1) than women with less education. For women who lived ≤ 2.5 km from the health facility, the estimated odds of health facility delivery (OR = 2.4, 95% CI = 1.5-4.1) and postnatal care visit (OR = 1.6, 95% CI = 1.0-2.6) were higher than for those who lived > 2.5 km away. Compared with baseline, a higher percentage of survey participants at follow-up were able to demonstrate proper handwashing (P = 0.001); water treatment behavior did not change. This evaluation suggested that hygiene, nutritional, clean delivery incentives, higher education level, and geographical contiguity to health facility were associated with increased use of maternal health services by pregnant women.

The Relationship Between Distance to Water Source and Moderate-to-Severe Diarrhea in the Global Enterics Multi-Center Study in Kenya, 2008-2011.

In the developing world, fetching water for drinking and other household uses is a substantial burden that affects water quantity and quality in the household. We used logistic regression to examine whether reported household water fetching times were a risk factor for moderate-to-severe diarrhea (MSD) using case-control data of 3,359 households from the Global Enterics Multi-Center Study in Kenya in 2009-2011. We collected additional global positioning system (GPS) data for a subset of 254 randomly selected households and compared GPS-based straight line and actual travel path distances to fetching times reported by respondents. GPS-based data were highly correlated with respondent-provided times (Spearman correlation coefficient = 0.81, P < 0.0001). The median estimated one-way distance to water source was 200 m for cases and 171 for controls (Wilcoxon rank sums/Mann-Whitney P = 0.21). A round-trip fetching time of > 30 minutes was reported by 25% of cases versus 15% of controls and was significantly associated with MSD where rainwater was not used in the last 2 weeks (odds ratio = 1.97, 95% confidence interval = 1.56-2.49). These data support the United Nations definition of access to an improved water source being within 30 minutes total round-trip travel time.

Cholera at the crossroads: the association between endemic cholera and national access to improved water sources and sanitation.

We evaluated World Health Organization (WHO) national water and sanitation coverage levels and the infant mortality rate as predictors of endemic cholera in the 5-year period following water and sanitation coverage estimates using logistic regression, receiver operator characteristic curves, and different definitions of endemicity. Each was a significant predictors of endemic cholera at P < 0.001. Using a value of 250 for annual cases reported in 3 of 5 years, a national water access level of 71% has 65% sensitivity and 65% specificity in predicting endemic cholera, a sanitation access level of 39% has 63% sensitivity and 62% specificity, and an infant mortality rate of 65/1,000 has 67% sensitivity and 69% specificity. Our findings reveal the tradeoff between sensitivity and specificity for these predictors of endemic cholera and highlight the substantial uncertainty in the data. More accurate global surveillance data will enable more precise characterization of the benefits of improved water and sanitation.

Laboratory-confirmed cholera and rotavirus among patients with acute diarrhea in four hospitals in Haiti, 2012-2013.

An outbreak of cholera began in Haiti in October of 2010. To understand the progression of epidemic cholera in Haiti, in April of 2012, we initiated laboratory-enhanced surveillance for diarrheal disease in four Haitian hospitals in three departments. At each site, we sampled up to 10 hospitalized patients each week with acute watery diarrhea. We tested 1,616 specimens collected from April 2, 2012 to March 28, 2013; 1,030 (63.7%) specimens yielded Vibrio cholerae, 13 (0.8%) specimens yielded Shigella, 6 (0.4%) specimens yielded Salmonella, and 63 (3.9%) specimens tested positive for rotavirus. Additionally, 13.5% of children < 5 years old tested positive for rotavirus. Of 1,030 V. cholerae isolates, 1,020 (99.0%) isolates were serotype Ogawa, 9 (0.9%) isolates were serotype Inaba, and 1 isolate was non-toxigenic V. cholerae O139. During 1 year of surveillance, toxigenic cholera continued to be the main cause of acute diarrhea in hospitalized patients, and rotavirus was an important cause of diarrhea-related hospitalizations in children.

Seroepidemiologic survey of epidemic cholera in Haiti to assess spectrum of illness and risk factors for severe disease.

To assess the spectrum of illness from toxigenic Vibrio cholerae O1 and risk factors for severe cholera in Haiti, we conducted a cross-sectional survey in a rural commune with more than 21,000 residents. During March 22-April 6, 2011, we interviewed 2,622 residents ≥ 2 years of age and tested serum specimens from 2,527 (96%) participants for vibriocidal and antibodies against cholera toxin; 18% of participants reported a cholera diagnosis, 39% had vibriocidal titers ≥ 320, and 64% had vibriocidal titers ≥ 80, suggesting widespread infection. Among seropositive participants (vibriocidal titers ≥ 320), 74.5% reported no diarrhea and 9.0% had severe cholera (reported receiving intravenous fluids and overnight hospitalization). This high burden of severe cholera is likely explained by the lack of pre-existing immunity in this population, although the virulence of the atypical El Tor strain causing the epidemic and other factors might also play a role.

Evaluation of a rapid cholera response activity--Nyanza Province, Kenya, 2008.

BACKGROUND: In response to recurrent cholera outbreaks in Nyanza Province, Kenya, a local nongovernmental organization assisted the Ministry of Health by providing cholera education activities to some cholera-affected communities. We evaluated the impact on cholera prevention knowledge and practices. METHODS: In November-December 2008, we conducted a cross-sectional household survey and tested stored water for chlorine in 6 cholera-affected enumeration areas (intervention-EAs) where response activities had occurred between March-September 2008, and 6 comparison-EAs with no known reports of cholera outbreaks or response activities. RESULTS: We enrolled 358 individuals from intervention-EAs and 365 from comparison-EAs. Overall, >80% knew cholera symptoms and over 60% knew that water treatment prevented diarrhea; <20% had chlorine residual in stored water. More intervention-EA respondents than comparison-EA respondents recalled a cholera outbreak in their community (52% vs 19%, P < .0001), and of those, 51% versus 39%, respectively, had attended a cholera response event. Detectable chlorine residuals in stored water were found in a higher percentage of intervention-EA and comparison-EA event attendees (21% and 25%, respectively) than nonattendees (17% and 8%, respectively). CONCLUSIONS: There was a gap between knowledge and practice of water treatment as a cholera preventive measure. Cholera event attendance may have modestly motivated increased household water treatment.

Neurologic manifestations associated with an outbreak of typhoid fever, Malawi--Mozambique, 2009: an epidemiologic investigation.

BACKGROUND: The bacterium Salmonella enterica serovar Typhi causes typhoid fever, which is typically associated with fever and abdominal pain. An outbreak of typhoid fever in Malawi-Mozambique in 2009 was notable for a high proportion of neurologic illness. OBJECTIVE: Describe neurologic features complicating typhoid fever during an outbreak in Malawi-Mozambique METHODS: Persons meeting a clinical case definition were identified through surveillance, with laboratory confirmation of typhoid by antibody testing or blood/stool culture. We gathered demographic and clinical information, examined patients, and evaluated a subset of patients 11 months after onset. A sample of persons with and without neurologic signs was tested for vitamin B6 and B12 levels and urinary thiocyanate. RESULTS: Between March - November 2009, 303 cases of typhoid fever were identified. Forty (13%) persons had objective neurologic findings, including 14 confirmed by culture/serology; 27 (68%) were hospitalized, and 5 (13%) died. Seventeen (43%) had a constellation of upper motor neuron findings, including hyperreflexia, spasticity, or sustained ankle clonus. Other neurologic features included ataxia (22, 55%), parkinsonism (8, 20%), and tremors (4, 10%). Brain MRI of 3 (ages 5, 7, and 18 years) demonstrated cerebral atrophy but no other abnormalities. Of 13 patients re-evaluated 11 months later, 11 recovered completely, and 2 had persistent hyperreflexia and ataxia. Vitamin B6 levels were markedly low in typhoid fever patients both with and without neurologic signs. CONCLUSIONS: Neurologic signs may complicate typhoid fever, and the diagnosis should be considered in persons with acute febrile neurologic illness in endemic areas.

Impact of a hygiene curriculum and the installation of simple handwashing and drinking water stations in rural Kenyan primary schools on student health and hygiene practices.

School-based hygiene and water treatment programs increase student knowledge, improve hygiene, and decrease absenteeism, however health impact studies of these programs are lacking. We collected baseline information from students in 42 schools in Kenya. We then instituted a curriculum on safe water and hand hygiene and installed water stations in half ("intervention schools"). One year later, we implemented the intervention in remaining schools. Through biweekly student household visits and two annual surveys, we compared the effect of the intervention on hygiene practices and reported student illness. We saw improvement in proper handwashing techniques after the school program was introduced. We observed a decrease in the median percentage of students with acute respiratory illness among those exposed to the program; no decrease in acute diarrhea was seen. Students in this school program exhibited sustained improvement in hygiene knowledge and a decreased risk of respiratory infections after the intervention.

A strategy to increase adoption of locally-produced, ceramic cookstoves in rural Kenyan households.

BACKGROUND: Exposure to household air pollutants released during cooking has been linked to numerous adverse health outcomes among residents of rural areas in low-income countries. Improved cookstoves are one of few available interventions, but achieving equity in cookstove access has been challenging. Therefore, innovative approaches are needed. To evaluate a project designed to motivate adoption of locally-produced, ceramic cookstoves (upesi jiko) in an impoverished, rural African population, we assessed the perceived benefits of the cookstoves (in monetary and time-savings terms), the rate of cookstove adoption, and the equity of adoption. METHODS: The project was conducted in 60 rural Kenyan villages in 2008 and 2009. Baseline (n = 1250) and follow-up (n = 293) surveys and a stove-tracking database were analyzed. RESULTS: At baseline, nearly all respondents used wood (95%) and firepits (99%) for cooking; 98% desired smoke reductions. Households with upesi jiko subsequently spent <100 Kenyan Shillings/week on firewood more often (40%) than households without upesi jiko (20%) (p = 0.0002). There were no significant differences in the presence of children <2 years of age in households using upesi jiko (48%) or three-stone stoves (49%) (p = 0.88); children 2-5 years of age were less common in households using upesi jiko versus three-stone stoves (46% and 69%, respectively) (p = 0.0001). Vendors installed 1,124 upesi jiko in 757 multi-family households in 18 months; 68% of these transactions involved incentives for vendors and purchasers. Relatively few (<10%) upesi jiko were installed in households of women in the youngest age quartile (<22 years) or among households in the poorest quintile. CONCLUSIONS: Our strategy of training of local vendors, appropriate incentives, and product integration effectively accelerated cookstove adoption into a large number of households. The strategy also created opportunities to reinforce health messages and promote cookstoves sales and installation. However, the project's overall success was diminished by inequitable and incomplete adoption by households with the lowest socioeconomic status and young children present. Additional evaluations of similar strategies will be needed to determine whether our strategy can be applied equitably elsewhere, and whether reductions in fuel use, household air pollution, and the incidence of respiratory diseases will follow adoption of improved cookstoves.

Impact of integration of hygiene kit distribution with routine immunizations on infant vaccine coverage and water treatment and handwashing practices of Kenyan mothers.

Integration of immunizations with hygiene interventions may improve use of both interventions. We interviewed 1361 intervention and 1139 comparison caregivers about hygiene practices and vaccination history, distributed water treatment and hygiene kits to caregivers during infant vaccination sessions in intervention clinics for 12 months, and conducted a followup survey of 2361 intervention and 1033 comparison caregivers. We observed significant increases in reported household water treatment (30% vs 44%, P < .0001) and correct handwashing technique (25% vs 51%, P < .0001) in intervention households and no changes in comparison households. Immunization coverage improved in both intervention and comparison infants (57% vs 66%, P = .04; 37% vs 53%, P < .0001, respectively). Hygiene kit distribution during routine immunizations positively impacted household water treatment and hygiene without a negative impact on vaccination coverage. Further study is needed to assess hygiene incentives, implement alternative water quality indicators, and evaluate the impact of this intervention in other settings.

Integration of routine vaccination and hygiene interventions: a comparison of 2 strategies in Kenya.

BACKGROUND: Hygiene interventions reduce child mortality from diarrhea. Vaccination visits provide a platform for delivery of other health services but may overburden nurses. We compared 2 strategies to integrate hygiene interventions with vaccinations in Kenya's Homa Bay district, 1 using community workers to support nurses and 1 using nurses. METHODS: Homa Bay was divided into 2 geographical areas, each with 9 clinics. Each area was randomly assigned to either the nurse or community-assisted strategy. At infant vaccination visits hygiene kits were distributed by the nurse or community member. Surveys pre- and post-intervention, measured hygiene indicators and vaccination coverage. Interviews and focus groups assessed acceptability. RESULTS: Between April 2009 and March 2010, 39 158 hygiene kits were distributed. Both nurse and community-assisted strategies were well-accepted. Hygiene indicators improved similarly in nurse and community sites. However, residual chlorine in water changed in neither group. Vaccination coverage increased in urban areas. In rural areas coverage either remained unchanged or increased with 1 exception (13% third dose poliovirus vaccine decrease). CONCLUSIONS: Distribution of hygiene products and education during vaccination visits was found to be feasible using both delivery strategies. Additional studies should consider assessing the use of community members to support integrated service delivery.

Multidrug-resistant typhoid fever with neurologic findings on the Malawi-Mozambique border.

BACKGROUND: Salmonella enterica serovar Typhi causes an estimated 22 million cases of typhoid fever and 216 000 deaths annually worldwide. We investigated an outbreak of unexplained febrile illnesses with neurologic findings, determined to be typhoid fever, along the Malawi-Mozambique border. METHODS: The investigation included active surveillance, interviews, examinations of ill and convalescent persons, medical chart reviews, and laboratory testing. Classification as a suspected case required fever and ≥1 other finding (eg, headache or abdominal pain); a probable case required fever and a positive rapid immunoglobulin M antibody test for typhoid (TUBEX TF); a confirmed case required isolation of Salmonella Typhi from blood or stool. Isolates underwent antimicrobial susceptibility testing and subtyping by pulsed-field gel electrophoresis (PFGE). RESULTS: We identified 303 cases from 18 villages with onset during March-November 2009; 214 were suspected, 43 were probable, and 46 were confirmed cases. Forty patients presented with focal neurologic abnormalities, including a constellation of upper motor neuron signs (n = 19), ataxia (n = 22), and parkinsonism (n = 8). Eleven patients died. All 42 isolates tested were resistant to ampicillin, chloramphenicol, and trimethoprim-sulfamethoxazole; 4 were also resistant to nalidixic acid. Thirty-five of 42 isolates were indistinguishable by PFGE. CONCLUSIONS: The unusual neurologic manifestations posed a diagnostic challenge that was resolved through rapid typhoid antibody testing in the field and subsequent blood culture confirmation in the Malawi national reference laboratory. Extending laboratory diagnostic capacity, including blood culture, to populations at risk for typhoid fever in Africa will improve outbreak detection, response, and clinical treatment.

Ciprofloxacin-resistant Salmonella enterica Serotype Typhi, United States, 1999-2008.

We report 9 ciprofloxacin-resistant Salmonella enterica serotype Typhi isolates submitted to the US National Antimicrobial Resistance Monitoring System during 1999-2008. The first 2 had indistinguishable pulsed-field gel electrophoresis patterns and identical gyrA and parC mutations. Eight of the 9 patients had traveled to India within 30 days before illness onset.

Variability in hand contamination based on serial measurements: implications for assessment of hand-cleansing behavior and disease risk.

Measuring hand contamination at critical times, such as eating, can be challenging. We examined whether hand contamination measured at random, such as on arrival (initial), predicts contamination at critical times. Mothers of young children in Bangladesh rinsed both hands in 200 mL of Ringer's solution. We compared results of serial samples with respect to fecal coliform counts. Among 39 mothers, the geometric mean of fecal coliforms was 307 colony-forming units (cfu)/100 mL at initial collection and 3,001 cfu/100 mL during critical times (P = 0.0006). There was no correlation between initial and critical time fecal coliform counts (R = 0.13, P = 0.43). The mean difference between initial and critical time counts was 3.5 (standard deviation = 1.4) on the log base-10 scale. Contamination of the same subjects' hands varied substantially within a few hours. Because hand contamination measured at random cannot reliably predict hand contamination at times of potential pathogen transmission, single random hand rinses are not valid proxy measures for handwashing behavior.

An outbreak of 2009 pandemic influenza A (H1N1) virus infection in an elementary school in Pennsylvania.

In May 2009, one of the earliest outbreaks of 2009 pandemic influenza A virus (pH1N1) infection resulted in the closure of a semi-rural Pennsylvania elementary school. Two sequential telephone surveys were administered to 1345 students (85% of the students enrolled in the school) and household members in 313 households to collect data on influenza-like illness (ILI). A total of 167 persons (12.4%) among those in the surveyed households, including 93 (24.0%) of the School A students, reported ILI. Students were 3.1 times more likely than were other household members to develop ILI (95% confidence interval [CI], 2.3-4.1). Fourth-grade students were more likely to be affected than were students in other grades (relative risk, 2.2; 95% CI, 1.2-3.9). pH1N1 was confirmed in 26 (72.2%) of the individuals tested by real-time reverse-transcriptase polymerase chain reaction. The outbreak did not resume upon the reopening of the school after the 7-day closure. This investigation found that pH1N1 outbreaks at schools can have substantial attack rates; however, grades and classrooms are affected variably. Additional study is warranted to determine the effectiveness of school closure during outbreaks.

Is structured observation a valid technique to measure handwashing behavior? Use of acceleration sensors embedded in soap to assess reactivity to structured observation.

Structured observation is often used to evaluate handwashing behavior. We assessed reactivity to structured observation in rural Bangladesh by distributing soap containing acceleration sensors and performing structured observation 4 days later. Sensors recorded the number of times soap was moved. In 45 participating households, the median number of sensor soap movements during the 5-hour time block on pre-observation days was 3.7 (range 0.3-10.6). During the structured observation, the median number of sensor soap movements was 5.0 (range 0-18.0), a 35% increase, P = 0.0004. Compared with the same 5-hour time block on pre-observation days, the number of sensor soap movements increased during structured observation by ≥ 20% in 62% of households, and by ≥ 100% in 22% of households. The increase in sensor soap movements during structured observation, compared with pre-observation days, indicates substantial reactivity to the presence of the observer. These findings call into question the validity of structured observation for measurement of handwashing behavior.