Benjamin Nygren

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.

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.

Foodborne outbreaks of shigellosis in the USA, 1998–2008

We examined reported outbreaks of foodborne shigellosis in the USA from 1998 to 2008 and summarized demographic and epidemiological characteristics of 120 confirmed outbreaks resulting in 6208 illnesses. Most reported foodborne shigellosis outbreaks (n = 70, 58%) and outbreak-associated illnesses (n = 3383, 54%) were restaurant-associated. The largest outbreaks were associated with commercially prepared foods distributed in multiple states and foods prepared in institutional settings. Foods commonly consumed raw were implicated in 29 (24%) outbreaks and infected food handlers in 28 (23%) outbreaks. Most outbreaks (n = 86, 72%) were caused by Shigella sonnei. Targeted efforts to reduce contamination during food handling at multiple points in the food processing and distribution system, including food preparation in restaurants and institutional settings, could prevent many foodborne disease outbreaks and outbreak-related illnesses including those due to Shigella.

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.

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.

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.

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

BackgroundExposure 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.MethodsThe 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.ResultsAt 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.ConclusionsOur 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.

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.