Asian Journal of Research in Infectious Diseases

Background: The emergence and the spread of the novel coronavirus or the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has caused a devastating impact on the economy and has become a pressing issue globally. Due to the significant increase in the number of confirmed cases and death tolls worldwide, and certain countries reporting second waves, there is an immediate need for an effective vaccine or other therapeutic intervention to control the spread of the disease. Improving our understanding on the host’s anti-viral immune response on SARS-CoV-2 infection, the potential immune evasion mechanisms adopted by the virus, and the speculated role of antibody dependent enhancement (ADE) in coronavirus disease 2019 (COVID-19) pathogenesis will aid in identifying and designing effective therapeutics.

Aim: This review aims to provide an in-depth view of the current knowledge available on the range of host defense mechanisms activated by SARS-CoV-2 infection and various immune evasion mechanisms utilized by the virus. In addition, it also highlights the postulated role of ADE in viral pathogenesis and covers the different preventive and therapeutic options available for the treatment of COVID-19 based on current literature.

Discussion: The ongoing COVID-19 pandemic serves as a timely reminder on the constant evolutionary process the virus undergoes to emerge as a novel strain and to spread undetected within the population. Similar to other infectious diseases, the host defence mechanism is triggered, and it plays a central role in dampening viral replication by recruiting immune cells and activating anti-viral mechanisms to control the spread of infection by SARS-CoV-2. However, the virus has adopted different immune evasion mechanisms to circumvent host surveillance to successfully establish infection. Hence, understanding the host’s immune responses triggered by SARS-CoV-2 infection is critical for identifying and designing novel and effective therapeutics. Currently, over 70% of the population are either asymptomatic or they showcase mild to moderate symptoms and reasons for why some people can mount immune responses more quickly than others are unknown. However, a growing body of research speculates that the ADE mechanism may facilitate the SARS-CoV-2 entry and can contribute to severe clinical manifestations. With the constant rise in the number of confirmed cases, there is an immediate need for an effective vaccine to mitigate the spread of the virus. Presently, there is no treatment for COVID-19 although several vaccine candidates are in clinical trials. Therefore, preventive measures like social distancing, isolation, and travel restrictions, may be the key to controlling the rapid spread of COVID-19.

Identifying the effects of temperature on coronavirus disease (COVID-19) outbreak is essential for modelling studies and guiding intervention strategies all over the world. The aim of the study is to understand the effect of temperature on global epidemic trends, geographic distribution, and transmission patterns of COVID-19. Data on COVID-19 and temperature from 1st February 2020 to 30th April 2020 were included. The epidemic trends we analyzed using both descriptive and inferential statistics; the growth of affected countries was by descriptive analysis; and the global distribution and transmission trend by inferential statistics. Scattered plot diagram matrix was performed for Europe and Africa data. Based on 90 days COVID-19 affected and death data survival analysis was performed for South East Asian region. Lowest three months average temperature was in Europe (41.06⁰F) from February 2020 to April 2020 (34.6⁰F, 41.1⁰F and 47.5⁰F) shows the highest average confirmed case. Highest three months avg. temperature was Africa (74.4⁰F) February 2020 to April 2020 (73.4⁰F, 74.7⁰F and 75.3⁰F) shows the lowest avg. confirmed case and avg. death. In Europe, average temperatures with transmission positively correlated on the other hand in Africa average with transmission were negatively correlated. The results of the study suggested that, temperature had positive or negative effects on the geographical trend of COVID-19 confirmed cases, death cases, recovered case or transmission. It is being suggested that geographical regions with a lower temperature need to adopt the stricter control measures and WHO is a guideline to prevent rapid spread of COVID-19.

Background: The sanitary state of the environment and general hygiene has long been known to play a critical role in the cause and spread of infectious diseases, be it directly or indirectly.   

Objective: This study was aimed at exploring the implications of some WASH practices on the prevalence of malaria infection among school children in Gombe State, Nigeria.

Methodology: A cross sectional survey design was employed to study 745 school children (aged 6 to 15 years) who were selected using a multi-stage sampling technique from 12 public and 6 private schools in six Local Government Areas (LGAs) of the State. Rapid Diagnostic Test (RDT) was used to screen the children for malaria. Descriptive statistics were generated to summarize research findings while chi square statistics was used to compare proportions at 0.05 significance levels. Risks were estimated using odd ratio (OR).

Results: The mean age of the pupils was 9.96±2.26 years and slightly more than half (50.9%) of them were males while the rest (49.1%) were females. Out of the 745 subjects only 101 (13.6%) tested positive for malaria.  And even though, 86.4% of them indicated availability of toilets in their residences, not all (98.6%) of them used the toilets. Slightly more than half (51.5%) of the participants dwell in houses without proper drainage while 46.7% reside in mud houses. Children from households without toilets had more than five times odds of having malaria (OR=5.230; 95% CI= 3.236-8.453, P=0.000). Furthermore, children from households that were sourcing their drinking water from streams, rivers and wells suffered more from malaria than those using portable/pipe borne water (OR=0.230, CI= 0.131-0.405, p=0.000). While children who dwelt in cement houses had less odds of malaria infection (OR=0.270, 95% CI=0.169-0.431, P=0.000), those who dwelt in houses without drainages had more than twice odds of malaria infection (OR=2.642, 95% CI= 1.671- 4.176). Again, proper waste disposal was associated with lower odds of malaria infection.

Conclusion: The findings of this study suggests the existence of association between selected WASH practices and malaria prevalence among the school children. This should inform an integrated WASH and malaria advocacy as well as high level engagement with concerned authorities and communities.

Enterococci despite being a normal commensal is of great health concern since it can become virulent. Hence the study investigated the prevalence of Enterococci infection and two tertiary health institutions (Enugu State University of Technology (ESUT) Teaching Hospital, Parklane and University of Nigeria Teaching Hospital (UNTH), Ituku/Ozalla in Enugu State) were used. Isolation and identification were based on standard procedures and biochemical tests. The results showed that age ranges of 21-25years 10(14.7%) and 26-30 years 8(11.8%) had the highest prevalence. Also, more females were infected by the organism than males though the difference was not statistically significant (p= 0.371).The possible predisposing factor showed that 16(23.5%) were unknown while 10(14.7%), 6(8.8%), 14(20.6%), 9(13.2%), 8(11.8%) and 5(7.6%) were catheterization, surgery, pregnancy, Diabetes, HIV/AIDS and previous history of enterococcal infection, respectively. The frequency of enterococcal isolates from different specimens showed that 24(35.3%) of the isolates were from urine samples, 12(17.6%) were from high vaginal swab, 7(10.2%) were from ear swab and wound swab respectively, 4(5.9%) were from urethral swab and aspirates respectively and 2(2.9%) were from sputum samples. Furthermore, departmental sources of enterococcus sp. isolated showed that 21(30.9%) were from Surgery department followed by general out-patients department 14(20.6%), Urology 8(10.3%), Gynaecology 7(10.3), Medicine 6(8.8%), Antenatal, Children out-patients, Neurology and Children Emergency Department had 3(4.4%) each. Also, 41(60.3%) out of the 68 isolates were nosocomially acquired and 27(39.7%) isolates were community acquired. There was no significant difference (p= 0.486) when nosocomially acquired enterococcal isolates were compared with community acquired enterococcal isolates. Monthly frequencies of the isolates showed that July had the highest frequency 10(14.7%) followed by the month of May 7(10.3%). April, August and October had 6(8.8%) respectively. February, March November and December had 5(7.4) respectively; January and September had 4(5.9%) respectively while June had 3(4.4%). Seasonal comparison (rainy and dry season) of the distribution of the isolates within the years of the study showed that rainy season had 38 number of isolates while dry season had 30 number of isolates and there was no significant difference between the frequencies of occurrence in the two seasons (p= 0.271). Therefore, there is an increasing prevalence of Enterococci and can be hospital acquired, screening for this organism is important in hospital setting.

Under-five mortality is among the major public health problems in developing countries, the rate of which is an important factor for a country’s development. For this reason, under-five mortality status is an important outcome to measure for children’s health. This study uses the Cox proportional-hazards model to identify risk factors associated with under-five mortality in Sudan. This study uses the 2014 Sudan Multiple Indicator Cluster Survey (MICS) conducted by the Central Bureau of Statistics in collaboration with several national institutions. The survival Cox proportional-hazards model was used to identify factors that affect under-five child mortality in Sudan. The results show that the weight of a child at birth is positively associated with the under-five child mortality rate. Under-five children who have both small and large weights at birth are at a higher risk of dying before reaching five years. Based on demographic factors associated with under-five mortality, our analysis showed that mothers who were married at the time of the survey are most likely to have higher under-five child mortality as compared to formerly married mothers. In addition to this, that mother’s age at the time of the birth is significantly associated with under-five mortality. Based on the result, the lack of important policies targeting the reduction of socioeconomic inequalities between rural and urban areas is the major problem of public health interventions to improve child health and survival in Sudan.