Seroprevalence of SARS-CoV-2 antibodies and associated risk factors during the second wave of infection in a university community in Cameroon.

Background: The COVID-19 pandemic has caused a public health emergency in all sectors of society, including universities and other academic institutions in Cameroon. However, little is known concerning the real prevalence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infections among student communities during the second wave of infection in Cameroon. This study aimed to estimate SARS-CoV-2 antibodies seroprevalence among participants in a university community in Cameroon. Methodology: A cross-sectional study was conducted from March to April 2021 in 547 students aged ≥18 years during a mass diagnostic campaign at the School of Health Sciences of the Catholic University of Central Africa (ESS/UCAC). The anti-SARS-CoV-2 antibody screening was done using the Panbio™ COVID-19 IgG/IgM Rapid Diagnostic Test. Results: The overall seroprevalence of SARS-CoV-2 antibodies was 27%, of which 89.9% (n = 133) was IgG, 6.7% (n = 10) IgM and 3.4% (n = 5) IgG/IgM positive. The undergraduate students represented 79% (432/547) of the total population and were highly positive with anti-SARS-CoV-2 antibodies 30% (130/432) as compared with postgraduate students 20% (23/115). The total antibody seropositivity was higher in males (34.4%) than females (24.9%). Several factors were associated with an increased risk of SARS-CoV-2 seroprevalence including the male gender (OR: 1.61 [95% confidence interval, CI 1.0-2.4]), specialization to medical laboratory (OR: 2.8 [95% CI 1.1-7.1]) and nursing sciences (OR: 2.6 [95% CI 1.1-6.2]). Conclusion: Our findings point to extensive and underreported circulation of SARS-CoV-2 in a university community during the second wave of infection in Cameroon, which likely resulted in artificially low case counts.

[Residual risk for transfusion-transmitted hepatitis B virus infection due to occult hepatitis B virus infection in donors living in Yaoundé, Cameroon]. / Risque résiduel de la transmission par transfusion de l´infection du virus de l´hépatite B dû aux donneurs porteurs de l´infection du virus de l´hépatite B occulte à Yaoundé, Cameroun.

INTRODUCTION: viral infection caused by hepatitis B virus is the most frequent transfusion-transmitted viral infection. Although the search for hepatitis B surface antigen (HBsAg) in blood banks has significantly reduced the risk for transfusion-transmitted virus infection, there is still a residual transfusion risk of transmission from donors with occult hepatitis B. Blood bags containing aHBc with or without aHBs and viral DNA can cause infections and represent a threat to transfusion safety when aHBc levels are undetectable. The purpose of this study is to determine the residual risk for transfusion-transmitted hepatitis B virus at the Central Hospital of Yaoundé (CHY) as well as at the St Martin de Porres's Catholic Hospital (SMPCH) in Yaoundé, Cameroon. METHODS: we conducted a cross-sectional study among blood donors at the Central Hospital of Yaoundé (CHY) and the St Martin de Porres's Catholic Hospital. In these subjects the search for aHBc and/or the aHBs was conducted by immunochromatography. HBV DNA test was performed on blood samples tested positive for aHBc and/or aHBs by Polymerase Chain Reaction (PCR) technique using specific primers. RESULTS: out of a total of 193 blood donors negative for HIV, HBV (HBsAg), HCV serological markers and treponema infections, the overall seroprevalence of aHBc and/or aHBs was 9,84% (19/193). Out of a total of 19 potentially infected donors, HBV DNA was detected in 03 individuals, including 02 aHBc carriers and 01 carrier of both aHBc and aHBs, reflecting a prevalence of occult hepatitis B of 15,79% (3/19) [IC 95% =3,38%-39,58%] and a residual risk for transfusion-transmitted hepatitis B virus of 1,55% (3/193) [IC 95% =0,32%-4,48%]. CONCLUSION: this study shows that the residual risk for transfusion-transmitted hepatitis B virus is low. However, it is recommended to screan blood donors for aHBc and/or aHBs.

An ultrasound-based referential of body height-adjusted normal liver organometry in school children from Bokito in rural Cameroon.

The grading system for ultrasonographic assessment of Schistosoma mansoni morbidity is crucial for evaluation of control programs. This requires prior definition of normal liver organometric ranges in the population from the endemic area. A cross-sectional study was conducted in a S. mansoni endemic area in rural Cameroon. 1002 Participants were screened and 234 of them, free from all common liver-affecting diseases in the area (schistosomiasis, malaria, hepatitis B and C) and with no ultrasonographic signs of liver disease were selected and their liver parameters measured by ultrasonography. All statistics were considered significant for p-values < 0.05. Normal dimensions of livers lobe sizes, portal vein wall thickness and portal vein diameters are reported. The liver organometric data are presented for the entire study population as a whole and separately for males and females as prediction plots, with observed values and fitted regression line with 95% confidence. Reference ranges for liver parameters (size, portal vein thickness and diameter) adjusted for body height established in the current study are novel for Cameroon. The prediction plots generated should improve the accuracy of the assessment of liver morbidity by ultrasonography in the region.

Antibiotic sensitivity profile of Staphylococcus aureus isolated from HIV/AIDS patients presenting with pyoderma, at the Yaounde Central Hospital, Cameroon.

INTRODUCTION: the purpose of this study was to evaluate the in vitro activity of several antibiotics against strains of Staphylococcus aureus isolated from pyoderma in people living with Human Immunodeficiency Virus (HIV), consulting at the day clinic of the Yaoundé Central Hospital. METHODS: this was a prospective, cross-sectional study which was carried out in five months (November 2013-March 2014). Fifty-three (53) pus specimens were collected; from which the isolation of Staphylococcus aureus was made using Chapman agar. Mannitol fermentation, catalase, coagulase and DNase tests were used for species identification. Antibiotic sensitivity of each strain was determined by the agar diffusion method. RESULTS: forty-eight (48) strains of Staphylococcus aureus were isolated (90.56%). A high rate of sensitivity to antibiotics was observed in many strains: vancomycin (100.0%), pristinamycin (100.0%), chloramphenicol (100.0%), oxacillin (97.9%), cefoxitin (97.9%), gentamicin (87.5%), tobramycin (83.3%). However, some strains had strong resistance to penicillin G (89.6%) and cotrimoxazole (64.6%). The proportion of Methicilin Resistant strains of Staphylococcus aureus (MRSA) was low (2.0%). The kanamycin-tobramycin-gentamycin phenotype (KTG) was most common in the aminoglycosides resistant strains; the same as the induced phenotype E stains (iMLSB) in macrolides resistant strains. Conclusion: these results indicate that many of these antibiotics tested are still effective against strains of Staphylococcus aureus.

Negative Association of Interleukin-33 Plasma Levels and Schistosomiasis Infection in a Site of Polyparasitism in Rural Cameroon.

Background: This study aimed to investigate the association of plasma levels of IL-33, a mucosal alarmin known to elicit type-2 immunity, with infection and liver fibrosis profiles of school children from an endemic area for Schistosoma mansoni, malaria and hepatitis (B & C) in rural Cameroon. Methods: A cross-sectional study enrolling schoolchildren from 5 public schools was conducted. Single schistosomiasis, malaria and hepatitis infections or co-infections were assessed by kato katz, microscopy, and rapid diagnostic tests, respectively. Hepatic fibrosis was assessed by ultrasound according to WHO Niamey guidelines and plasma levels of Interleukin 33 were determined by ELISA. All statistics were performed using R studio software. Principal findings: We found a prevalence of 13.5% (37/275), 18.2% (50/275), and 8% (22/275), respectively for schistosomiasis, malaria and hepatitis (B or C) single infections. Only 7.6% (21/275) of co-infections were reported. Although Plasma IL-33 showed a minimal negative risk for schistosomiasis infection (AOR 0.99; 95% CI 0.97-1.01), S. mansoni infected participants had lower levels of plasma IL-33 (p = 0.003) which decreased significantly as eggs burdens increased (p = 0.01) with a negative Pearson coefficient of r = -0.22. Hepatic fibrosis occurred in 47.3% (130/275) of our study population independently from plasma levels of IL-33 (AOR 1.00; 95% CI 0.99-1.01). Conclusion/Significance: Our data failed to show an association between plasma IL-33 levels and liver disease but convincingly report on a negative association between plasma IL-33 levels and schistosomiasis infection and egg burden in school children from a polyparasitic schistosomiasis endemic area.

Antibiotic susceptibility patterns of Staphylococcus aureus strains isolated at the Yaounde Central Hospital, Cameroon: a retro prospective study.

INTRODUCTION: Staphylococcus aureus is an important pathogen responsible for hospital and community acquired infection(s). Emerging resistance to methicillin in this organism has left physicians with few therapeutic alternatives to treat infections caused by it. This study was aimed at determining the antibiotic susceptibility patterns of Staphylococcus aureus strains isolated at the Yaounde Central Hospital, Cameroon. METHODS: from January 2014 to November 2016, a total of 250 non repeated strains were isolated from various clinical specimens. Isolates and antibiotic susceptibility profiles were identified through standard microbiological techniques. RESULTS: methicillin-resistant Staphylococcus aureus (MRSA) and methicillin-sensitive Staphylococcus aureus (MSSA) accounted respectively for 80% (201/205) and 20% (49/205) of the total strains isolated. MRSA strains displayed high resistance to cefoxitin (100%), cotrimoxazole (89%), vancomycin (79.7%), lincomycin (70.3%), tobramycin (72.5%), doxycycline (68.0%), kanamycin (69.7%) and erythromycin (55.7%). In contrast, a high susceptibility was observed with rifampicin (82.6%). KTG (42.3%) and constitutive MLSB (17.4%) were the most frequent phenotypes recorded. CONCLUSION: our results show that the carriage of acquired MRSA infections predominates in this population. Despite the noticeable multiresistance of MRSA strains to antibiotics, rifampicin remains the drugs of choice for the therapy of acquired MRSA infections in this setting. In order to slow down antimicrobial resistance, surveillance studies for antimicrobial susceptibility remains essential to identify resistance and inform policy on resistance.

Prevalence and risk factors of HTLV-1/2 and other blood borne infectious diseases among blood donors in Yaounde Central Hospital, Cameroon.

INTRODUCTION: Transfusion-transmissible infectious microorganisms including bacteria and viruses are among the greatest threats to blood safety for the recipient. The prevalence and risk factors of HTLV-1/2 and other blood borne infectious diseases were determined among blood donors in Yaounde Central Hospital, Cameroon. METHODS: Design: cross sectional study. Setting: The blood bank unit of Yaounde Central Hospital, Cameroon. Subjects: a consecutive sample of 265 apparently healthy adult blood donors. Investigations: Search for the presence of hepatitis B surface antigen (AgHBs) and antibodies to human T-lymphotropic virus type 1 (anti-HTLV-1/2), human immunodeficiency virus (anti-HIV), hepatitis C virus (anti-HCV) and syphilis and to determine the epidemiological correlates, if any, in the occurrence of HTLV infection. RESULTS: 77 (29.05%) of the blood donors had serological evidence of infection with at least one pathogen and 4 (5.2%) had dual infections with HTLV-1/2. The overall prevalence of HTLV-1/2, HIV, HCV, HBV and syphilis were 5.7%, 5.3%, 2.6%, 11.7%, 3.8% respectively. Surgical history (Chi2=4.785; P=0.029), scarification (Chi2=6.359; P = 0.012), piercing (Chi2 = 16.353; P = 0.000) and intravenous drug use (Chi2 = 15.660; P = 0.000) were identified as risk factors for HTLV-1/2 infection. CONCLUSION: A relative high prevalence of viral infections and syphilis was recorded among the study participants especially for HTLV-1/2 for which none blood donation is routine screened in our set up. Therefore, a routine screen of blood prior to transfusion should include anti-HTLV-1/2 tests.

Antibiotics susceptibility pattern of Streptococcus pneumoniae isolated from sputum cultures of human immunodeficiency virus infected patients in Yaoundé, Cameroon.

INTRODUCTION: The susceptibility of Streptococcus pneumoniae to commonly used antibiotics is threatened by the emergence of resistance of S. pneumonia strains. So, to improve the management of lower respiratory tract infections (LRTIs) in human immunodeficiency virus infected patients, we assessed the antibiotic susceptibility of Streptococcus pneumoniae which is the most common bacterial cause of LRTIs in patients. METHODS: A cross sectional study was carried out from May to October 2014. HIV infected patients suspected of LRTIs attending the Center Medical laboratory and those followed up at the authorized treatment center of Yaounde Military Hospital in Cameroon were enrolled. Sputum was collected from each patient and cultured; identification of microorganisms was performed following standard methods. The disk diffusion method was used for antibacterial susceptibility testing according to the Antibiogram Committee of French Society for Microbiology guidelines. RESULTS: A total of 51 (25.5%) isolates of S. pneumoniae were recovered from sputum samples obtained from 200 HIV infected patients aged 19-66 years old (mean age: 36±10.087 years old); 144 (72%) of them were female (sex ratio M/F: 1/3). S. pneumoniae carriage was not age dependent (P = 0.384) and was significantly higher in male compared to female (P = 0.008). S. pneumoniae isolates were susceptible to amoxicillin-clavulinic acid (100%), pristinamycin (100%), erythromycin (100%) and cefixime (98.04 %). Highest resistance rates were recorded with fusidic acid (100%), fosfomycin (100%) and tetracyclin (100%). CONCLUSION: S. pneumoniae is still susceptible to some agents in our study area however; ongoing surveillance for antimicrobial susceptibility remains essential to identify emerging resistance and attempt to limit its spread.

Prevalence and Identification of Serum Markers Associated with Vertical Transmission of Hepatitis B in Pregnant Women in Yaounde, Cameroon.

OBJECTIVE: To determine the prevalence of Hepatitis B Virus (HBV) infection in pregnant women and identify markers associated with vertical transmission of HBV. METHODS: Prospective and cross-sectional study over 10 months on 298 pregnant women attending antenatal clinics in the Cité Verte and Efoulan District hospitals in Cameroon. A dry tube blood collection was performed on all pregnant women and babies born to HBsAg-positive mothers. Serum from the women was used to test for HBsAg through immunochromatography and then confirmed by ELISA. The test for HBeAg, HBeAb and HBcAb and dosage of transaminases were performed on the serum of HBsAg-positive women. Only HBsAg was tested in babies within 24 hours after birth. RESULTS: HBsAg was present in 23 (7.7%) mothers while 275 (92.3%) tested negative. Due to loss to follow-up, we assessed vertical transmission in 20 babies born to20 mothers. In all, eight babies tested HBsAg-positive; six mothers tested positive with HBeAg; 10 mothers with HBeAb and two were simultaneously infected with HBV and HIV. CONCLUSION AND GLOBAL HEALTH IMPLICATIONS: HBeAg and increase in liver transaminases were serum markers associated with the vertical transmission of HBV while HBeAb and anti-HIV therapy were protective markers. There is need to systematically screen all pregnant women for hepatitis B, follow up those that are positive, and administer a dose of gammaglobulin anti-HBs to their children to reduce the risks of chronic hepatitis and hepatocellular carcinoma (CHC) and curb mortality and morbidity due to viral hepatitis B.

Antifungals susceptibility pattern of Candida spp. isolated from female genital tract at the Yaoundé Bethesda Hospital in Cameroon.

INTRODUCTION: Vaginal candidiasis is considered as an important public health problem worldwide and its incidence has increased nowadays. In recent years, inappropriate and disproportionate use of antifungal drugs, automedication as well as non compliance have caused drug resistance. METHODS: This study aimed at determining the in vitro antifungal susceptibility patterns of Candida speciesisolated from female genital tract at Yaoundé Bethesda Hospital in Cameroon. Two hundred and fourthy five women (age range: 15 years to 49 years) attending the hospital were recruited between January and June 2014 in this cross sectional study. Vaginal smears were collected using sterile swabs from each participant and cultured on sabouraud dextrose agar supplemented with chloramphenico l 0.5%; identification of Candida spp. was performed following standard methods. The disk diffusion method was used for antifungal susceptibility testing. RESULTS: Out of the 245 vaginal smears collected, 94 (38.4%) strains of yeast were isolates among which 43 (45.7%) were Candida albicans and 51 (54.3%) were non albicans. The highest susceptibility of the isolates was seen for nystatin 62 (83.78%), ketoconazole 61 (82.43%) and fluconazole 60 (81.08%). CONCLUSION: Despite the noticeable resistance of Candida spp. isolates to miconazole and itraconazole, the results indicate that nystatin, ketoconazole and fluconazole are the drugs of choice for the therapy of vaginal candidiasis in this region.

Bacteriological profile and antimicrobial susceptibility patterns of urine culture isolates from patients in Ndjamena, Chad.

INTRODUCTION: Bacteriological profile and antimicrobial susceptibility patterns of urine culture isolates were determined among patients in the Ndjamena General Hospital, a National Reference centre. METHODS: A cross-sectional study was carried out from July to November 2014. Six hundred and sixty patients were enrolled, to whom a cytobacteriological examination of urine was prescribed. Urine was collected and cultured. Bacterial identification and antimicrobial susceptibility patterns were performed using Vitek 2 compact automated system. RESULTS: 216 isolates were recovered from patients (age range: 10-90 years). E. coli was the pathogen frequently cultured 128 (59.3%) followed by K. pneumonia 28 (13.0%). Bacteriuria was more present in inpatients (70.4%) compared to outpatients (29.6%). High antibiotic-resistance rate (> 60%) of the total isolates was observed with ampicillin, ciprofloxacin and cephalosporins. Imipeneme (94.9%) displayed satisfactory activity against bacteria isolates. ESBLs phenotype was present in 68/105 (64.7%) of betalactamine resistant isolates. AAC(3)-I and AAC(6')-I enzymes were found respectively in 16/36 (44.4%) and 20/36 (55.6%) of aminoglycosides resistant isolates. Resistance of isolates to quinolones was mainly due to an association of target modification (gyrA and parC), porin reduction and/or efflux mechanisms and was present in 107/213 (49%) of quinolones resistant isolates. CONCLUSION: E. coli is the predominant uropathogen isolated in our setting and there are antibiotic-resistant uropathogens among the studied population. Therefore, routine surveillance of bacterial uropathogens to common used antibiotics must be a continuous process so as to provide physicians with up to date information about the local data of antimicrobial resistance.

Antifungals susceptibility pattern of Candida spp. isolated from female genital tract at the Yaoundé Bethesda Hospital in Cameroon

Introduction: vaginal candidiasis is considered as an important public health problem worldwide and its incidence has increased nowadays. In recent years, inappropriate and disproportionate use of antifungal drugs, automedication as well as non compliance have caused drug resistance.Methods: this study aimed at determining the in vitro antifungal susceptibility patterns of Candida species isolated from female genital tract at Yaoundé Bethesda Hospital in Cameroon. Two hundred and fourthy five women (age range: 15 years to 49 years) attending the hospital were recruited between January and June 2014 in this cross sectional study. Vaginal smears were collected using sterile swabs from each participant and cultured on sabouraud dextrose agar supplemented with chloramphenico l 0.5%; identification of Candida spp. was performed following standard methods. The disk diffusion method was used for antifungal susceptibility testing.Results: out of the 245 vaginal smears collected, 94 (38.4%) strains of yeast were isolates among which 43 (45.7%) were Candida albicans and 51 (54.3%) were non albicans. The highest susceptibility of the isolates was seen for nystatin 62 (83.78%), ketoconazole 61 (82.43%) and fluconazole 60 (81.08%).Conclusion: despite the noticeable resistance of Candida spp. isolates to miconazole and itraconazole, the results indicate that nystatin, ketoconazole and fluconazole are the drugs of choice for the therapy of vaginal candidiasis in this region

The Susceptibility Pattern of Salmonella Species to Commonly Used Antibiotics in the Bamenda District Health Area; Cameroon

The susceptibility of Salmonella bacteria to commonly used antibiotics such as ampicillin; chloramphenicol and trimethoprim/sulphamethoxazole is threatened by the emergence of resistance strains of Salmonella. A cross-sectional study was carried out from September 2014 to November 2014 in the Regional Hospital Bamenda on individuals presenting with symptoms of salmonellosis. The Salmonellae were isolated from stool by culturing in Salmonella-Shigella Agar and Kliger Iron Agar; the later in which the isolates produced specific biochemical characteristics which were conclusive. They were assessed for antimicrobial susceptibility by the disc diffusion method using Mueller-Hinton Agar following both CLSI and EUCAST manual instructions. A total of 253 samples were collected and 22 cases were positive for Salmonella species with a prevalence of 8.70%. The susceptibility of the isolated Salmonellae to seven antibiotics was noted with ciprofloxacin having an overall sensitivity of 52.38%; ofloxacin; 47.62%; ceftriaxone; 47.62%; and gentamicin; 38.10%. Chloramphenicol had a low sensitivity percentage of 28.57%; while co-trimoxazole and amoxicilin had a high resistance level of 100.00% (0% sensitivity). The fluoroquinolones were found to be the best drugs for the treatment of typhoid; but there was also a noticeable re-emergence of chloramphenicol susceptible Salmonella