Comprehensive profiling of social mixing patterns in resource poor countries: a mixed methods research protocol.

Background: Low-and-middle-income countries (LMICs) bear a disproportionate burden of communicable diseases. Social interaction data inform infectious disease models and disease prevention strategies. The variations in demographics and contact patterns across ages, cultures, and locations significantly impact infectious disease dynamics and pathogen transmission. LMICs lack sufficient social interaction data for infectious disease modeling. Methods: To address this gap, we will collect qualitative and quantitative data from eight study sites (encompassing both rural and urban settings) across Guatemala, India, Pakistan, and Mozambique. We will conduct focus group discussions and cognitive interviews to assess the feasibility and acceptability of our data collection tools at each site. Thematic and rapid analyses will help to identify key themes and categories through coding, guiding the design of quantitative data collection tools (enrollment survey, contact diaries, exit survey, and wearable proximity sensors) and the implementation of study procedures.We will create three age-specific contact matrices (physical, nonphysical, and both) at each study site using data from standardized contact diaries to characterize the patterns of social mixing. Regression analysis will be conducted to identify key drivers of contacts. We will comprehensively profile the frequency, duration, and intensity of infants' interactions with household members using high resolution data from the proximity sensors and calculating infants' proximity score (fraction of time spent by each household member in proximity with the infant, over the total infant contact time) for each household member. Discussion: Our qualitative data yielded insights into the perceptions and acceptability of contact diaries and wearable proximity sensors for collecting social mixing data in LMICs. The quantitative data will allow a more accurate representation of human interactions that lead to the transmission of pathogens through close contact in LMICs. Our findings will provide more appropriate social mixing data for parameterizing mathematical models of LMIC populations. Our study tools could be adapted for other studies.

Mycobacterium tuberculosis and nontuberculous mycobacterial isolates among patients with recent HIV infection in Mozambique.

OBJECTIVE: Mycobacteriosis is frequently diagnosed among HIV-infected patients. In Mozambique, where few patients are under antiretroviral therapy and the prevalence of tuberculosis is high, there is need for better characterization of mycobacteria at the species level, as well as for the identification of patterns of resistance to antituberculous drugs. METHODS: We studied a sample of 503 HIV-infected individuals suspected of having pulmonary tuberculosis. Of those 503, 320 tested positive for mycobacteria through sputum smear microscopy or culture of bronchoalveolar lavage fluid. RESULTS: Acid-fast bacilli were observed in the sputum of 73% of the individuals presenting positive cultures. Of 277 isolates tested, only 3 were nontuberculous mycobacteria: 2 were identified as Mycobacterium avium and one was identified as M. simiae. Strains initially characterized as M. tuberculosis complex through polymerase chain reaction restriction analysis (PRA) of the hsp65 gene were later confirmed as such through PRA of the gyrB gene. Among the M. tuberculosis isolates, resistance patterns were as follows: to isoniazid, 14%; to rifampin, 6%; and multidrug resistance, 5%. Previously treated cases showed significantly higher rates of resistance to first-line antituberculous drugs. The most common radiological pattern was interstitial infiltrate (in 67%), followed by mediastinal lymph node enlargement (in 30%), bronchiectasis (in 28%), miliary nodules (in 18%) and cavitation (in 12%). Patients infected with nontuberculous mycobacteria presented clinical profiles indistinguishable from those of other patients. The median CD4 lymphocyte count in this group was 134 cells/mm(3). CONCLUSIONS: There is a strong association between tuberculosis and AIDS in Mozambique, as expected in a country with a high prevalence of tuberculosis. Although drug resistance rates are high, the isoniazid-rifampin regimen continues to be the appropriate choice for initial therapy.

Doença pulmonar por Mycobacterium tuberculosis e micobactérias não-tuberculosas entre pacientes recém-diagnosticados como HIV positivos em Moçambique, África / Mycobacterium tuberculosis and nontuberculous mycobacterial isolates among patients with recent HIV infection in Mozambique

OBJECTIVE: Mycobacteriosis is frequently diagnosed among HIV-infected patients. In Mozambique, where few patients are under antiretroviral therapy and the prevalence of tuberculosis is high, there is need for better characterization of mycobacteria at the species level, as well as for the identification of patterns of resistance to antituberculous drugs. METHODS: We studied a sample of 503 HIV-infected individuals suspected of having pulmonary tuberculosis. Of those 503, 320 tested positive for mycobacteria through sputum smear microscopy or culture of bronchoalveolar lavage fluid. RESULTS: Acid-fast bacilli were observed in the sputum of 73 percent of the individuals presenting positive cultures. Of 277 isolates tested, only 3 were nontuberculous mycobacteria: 2 were identified as Mycobacterium avium and one was identified as M. simiae. Strains initially characterized as M. tuberculosis complex through polymerase chain reaction restriction analysis (PRA) of the hsp65 gene were later confirmed as such through PRA of the gyrB gene. Among the M. tuberculosis isolates, resistance patterns were as follows: to isoniazid, 14 percent; to rifampin, 6 percent; and multidrug resistance, 5 percent. Previously treated cases showed significantly higher rates of resistance to first-line antituberculous drugs. The most common radiological pattern was interstitial infiltrate (in 67 percent), followed by mediastinal lymph node enlargement (in 30 percent), bronchiectasis (in 28 percent), miliary nodules (in 18 percent) and cavitation (in 12 percent). Patients infected with nontuberculous mycobacteria presented clinical profiles indistinguishable from those of other patients. The median CD4 lymphocyte count in this group was 134 cells/mm³. CONCLUSIONS: There is a strong association between tuberculosis and AIDS in Mozambique, as expected in a country with a high prevalence of tuberculosis. Although drug resistance rates are high, the isoniazid-rifampin...

OBJETIVO: A micobacteriose é frequentemente diagnosticada entre pacientes infectados pelo HIV. Em Moçambique, onde apenas um pequeno número de pacientes encontra-se sob tratamento anti-retroviral, e a tuberculose tem alta prevalência, existe a necessidade de melhor caracterização destes agentes bacterianos, em nível de espécie, bem como de se caracterizar os padrões de resistência às drogas antituberculosas. MÉTODOS: Em uma coorte de 503 indivíduos HIV positivos suspeitos de tuberculose pulmonar, 320 apresentaram positividade para baciloscopia ou cultura no escarro e no lavado brônquico. RESULTADOS: Bacilos álcool-ácido resistentes foram detectados no escarro em 73 por cento dos casos com cultura positiva. De 277 isolados em cultura, apenas 3 mostraram-se tratar de micobactérias não-tuberculosas: 2 Mycobacterium avium e uma M. simiae. Todos os isolados de M. tuberculosis inicialmente caracterizados através de reação em cadeia de polimerase (RCP) do gene hsp65 foram posteriormente caracterizados como tal através de RCP do gene gyrB. Resistência à isoniazida foi encontrada em 14 por cento dos casos; à rifampicina em 6 por cento; e multirresistência em 5 por cento. Pacientes previamente tratados para tuberculose mostraram tendência a taxas maiores de resistência às drogas de primeira linha. O padrão radiológico mais freqüente encontrado foi o infiltrado intersticial (67 por cento), seguido da presença de linfonodos mediastinais (30 por cento), bronquiectasias (28 por cento), padrão miliar (18 por cento) e cavidades (12 por cento). Os pacientes infectados por micobactérias não-tuberculosas não apresentaram manifestações clínicas distintas das apresentadas pelos outros pacientes. A mediana de linfócitos CD4 entre todos os pacientes foi de 134 células/mm³. CONCLUSÕES: Tuberculose e AIDS em Moçambique estão fortemente associadas, como é de se esperar em países com alta prevalência de tuberculose. Embora as taxas de resistência a drogas sejam...