Face masks vs. COVID-19: a systematic review

The coronavirus disease (COVID-19) spread rapidly around the world. Two types of approaches have been applied to use of face masks as a tool to prevent the spread this disease in society. The aim of the systematic review was to assess the effectiveness of face masks against the novel coronavirus. A literature search was performed using different databases until April 30, 2020. Search terms were 'facemasks', 'novel coronavirus', and 'healthcare workers'. Five studies were included in the systematic review. A study stated that no difference between surgical and cotton masks. Also, two studies have emphasized the use of surgical masks or N95 respirators by medical staff, and two other studies emphasized the use of any type of face mask by general public. More studies in controlled contexts and studies of infections in healthcare and community places are needed for better definition of the effectiveness of face masks in preventing coronavirus.

La enfermedad por coronavirus (COVID-19) se propagó rápidamente por todo el mundo. Se han aplicado dos tipos de enfoques al uso de máscaras faciales como herramienta para prevenir la propagación de la enfermedad en la sociedad. El objetivo de la revisión sistemática fue evaluar la efectividad de las máscaras faciales contra el nuevo coronavirus. Se realizó una búsqueda bibliográfica utilizando diferentes bases de datos hasta el 30 de abril de 2020. Los términos de búsqueda fueron: 'máscaras faciales', 'nuevo coronavirus' y 'trabajadores de la salud'. Se incluyeron cinco estudios en la revisión sistemática. Un estudio indicó que no hay diferencia entre las máscaras quirúrgicas y las de algodón. Además, dos estudios han enfatizado el uso de máscaras quirúrgicas o respiradores N95 por parte del personal médico, y otros dos estudios enfatizaron el uso de cualquier tipo de mascarilla por parte del público en general. Se necesitan más estudios en contextos controlados y estudios de infecciones en el cuidado de la salud y en lugares comunitarios para una mejor aclaración de la efectividad de las mascarillas para prevenir el coronavirus.

A doença de coronavírus (COVID-19) se espalhou rapidamente por todo o mundo. Dois tipos de abordagens foram aplicados ao uso de máscaras faciais como uma ferramenta para impedir a propagação da doença na sociedade. O objetivo da revisão sistemática foi avaliar a eficácia das máscaras faciais contra o novo coronavírus. Uma pesquisa bibliográfica foi realizada usando diferentes bancos de dados até 30 de abril de 2020. Os termos de pesquisa foram: máscaras faciais ',' novo coronavírus 'e' profissionais de saúde '. Cinco estudos foram incluídos na revisão sistemática. Um estudo indicou que não há diferença entre máscaras cirúrgicas e máscaras de algodão. Além disso, dois estudos enfatizaram o uso de máscaras cirúrgicas ou respiradores N95 pelo pessoal médico e dois outros estudos enfatizaram o uso de qualquer tipo de máscara pelo público em geral. É necessário mais estudos em ambientes controlados e estudos de infecções nos serviços de saúde e na comunidade para esclarecer melhor a eficácia das máscaras na prevenção do coronavírus

Heat stress and physical capacity: a case study of semi-professional footballers

The aim of this study was to determine heat stress effect on physical capacity of semi-professional footballers in Iran by means of oxygen consumption measurement, heart rate monitoring and WBGT assessment environmental conditions. This study compared two different thermal environmental conditions related to sub-maximal exercise and its effect on human physical capacity. Thirty two male footballers [age 25.9 +/- 1.4 year; height 176 +/- 2.9 cm and weight 71 +/- 9.8 kg] were investigated under four workloads [50,100,150 and 200 W] in two different thermal conditions in the morning [WBGT=21°C] and afternoon [WBGT=33°C] in summer. Each test cycle lasted for 10 minutes with a 10 min interval for recovery and rest between every workload. In the end of each stage, the heart rate, blood pressure, skin temperature and oral temperature were measured and recorded. Expired air was collected and its volume was measured using standard Douglas bags. The WBGT index was also used to monitor the stressful heat condition. Heart rate and VO[2] consumption findings for different workload showed a significant difference between morning and afternoon [P<0.001]. HR and VO[2] consumption in both morning and afternoon courses showed a liner relation [r=0.88, r=0.9 respectively]. With increasing work load beside heat stress, heart rate and oxygen consumption increased. It is recommended that with Ta>35°C or WBGT>28°C, physical activates and performing exercises should be avoided in order to reduce the risk of heat stress-related conditions in athletes