Different epidemiological profiles in patients with Zika and dengue infection in Tapachula, Chiapas in Mexico (2016-2018): an observational, prospective cohort study.

BACKGROUND: The introduction of Zika and chikungunya to dengue hyperendemic regions increased interest in better understanding characteristics of these infections. We conducted a cohort study in Mexico to evaluate the natural history of Zika infection. We describe here the frequency of Zika, chikungunya and dengue virus infections immediately after Zika introduction in Mexico, and baseline characteristics of participants for each type of infection. METHODS: Prospective, observational cohort evaluating the natural history of Zika virus infection in the Mexico-Guatemala border area. Patients with fever, rash or both, meeting the modified criteria of PAHO for probable Zika cases were enrolled (June 2016-July 2018) and followed-up for 6 months. We collected data on sociodemographic, environmental exposure, clinical and laboratory characteristics. Diagnosis was established based on viral RNA identification in serum and urine samples using RT-PCR for Zika, chikungunya, and dengue. We describe the baseline sociodemographic and environmental exposure characteristics of participants according to diagnosis, and the frequency of these infections over a two-year period immediately after Zika introduction in Mexico. RESULTS: We enrolled 427 participants. Most patients (n = 307, 65.7%) had an acute illness episode with no identified pathogen (UIE), 37 (8%) Zika, 82 (17.6%) dengue, and 1 (0.2%) chikungunya. In 2016 Zika predominated, declined in 2017 and disappeared in 2018; while dengue increased after 2017. Patients with dengue were more likely to be men, younger, and with lower education than those with Zika and UIE. They also reported closer contact with water sources, and with other people diagnosed with dengue. Participants with Zika reported sexual exposure more frequently than people with dengue and UIE. Zika was more likely to be identified in urine while dengue was more likely found in blood in the first seven days of symptoms; but PCR results for both were similar at day 7-14 after symptom onset. CONCLUSIONS: During the first 2 years of Zika introduction to this dengue hyper-endemic region, frequency of Zika peaked and fell over a two-year period; while dengue progressively increased with a predominance in 2018. Different epidemiologic patterns between Zika, dengue and UIE were observed. Trial registration Clinical.Trials.gov (NCT02831699).

Micobacteriosis pulmonar por Mycobacterium kansasii / Micobacteriosis pulmonar por Mycobacterium kansasii

Micobacterias no tuberculosas (MNT) es una designación utilizada para referirse a un gran número de especies de micobacterias ambientales potencialmente patógenas y no patógenas, distintas de la Mycobacterium tuberculosis y Mycobacterium leprae. Mycobacterium kansasii (M. Kansasii) es una MNT oportunista causante de infecciones pulmonares, cutáneas, entre otras, cuya tasa de incidencia ha ido incrementando en los últimos años a nivel mundial. A través de presentar el siguiente caso se pretende aportar al conocimiento con respecto al abordaje de pacientes con infección por MNT a nivel pulmonar, dirigido a médicos que trabajan en atención primaria de salud (APS). Se trata del caso de una paciente de 46 años de edad que acude al Hospital Provincial General Docente de Riobamba (HPGDR) con infección por MNT a nivel pulmonar. En el examen microscópico se detectaron Bacilos­Ácido­Alcohol­Resistentes (BAAR) mientras en el cultivo de esputo más antibiograma se aisló M. kansasii resistente a los antibióticos utilizados para la terapia convencional de tuberculosis. Se trata de un caso raro en la práctica clínica. Es crucial saber cómo manejar una infección con M. kansasii debido a su implicación para la salud del paciente y el sistema de salud nacional. El médico de APS debe reconocer su papel fundamental y la importancia que tiene un diagnóstico oportuno y tratamiento adecuado.

Non­tuberculous mycobacteria (NTM) is a designation for a large number of mycobacterial species potentially pathogenous and non­pathogenous, different than Mycobacterium tuberculosis and Mycobacterium leprae. Mycobacterium kansasii (M. kansasii) is an opportunistic NTM that causes among other things, pulmonary and cutaneous infections, whose incidence is increasing worldwide. Trough the following case report we seek to provide a guide to physicians working on primary health care (PHC) on the management of patients with pulmonary infection caused by NTM. We report the case of a 46­year­old female patient who came to the Hospital Provincial General Docente de Riobamba (HPGDR) with a pulmonary infection caused by NTM. In the microscopic examination it was identified Acid­Fast Bacilli (AFB), meanwhile the microbiological culture and antibiogram it was isolated M. kansasii resistant to common antibiotics used for conventional tuberculosis therapy. It is a rare case in the clinical practice. It is crucial to know how to manage an infection with M. Kansasii due to its implication on the health of affected subjects and the national health system. A physician working on PHC has to know his/her fundamental role and the importance of an early diagnosis and adequate treatment.