Testing is one of the commendable measures for curbing the spread of coronavirus disease (COVID‐19). But, it should be done using the most appropriate specimen and an accurate diagnostic test such as ...real‐time reverse transcription‐polymerase chain reaction (qRT‐PCR). Therefore, a systematic review was conducted to determine the positive detection rate of severe acute respiratory syndrome coronavirus 2 (SARS‐CoV‐2) in different clinical specimens using qRT‐PCR. A total of 8136 pooled clinical specimens were analyzed to detect SARS‐CoV‐2, the majority were nasopharyngeal swabs (69.6%). A lower respiratory tract (LRT) specimens had a positive rate (PR) of 71.3% (95% confidence interval CI: 60.3%‐82.3%) while no virus was detected in the urinogenital specimens. Bronchoalveolar lavage fluid (BLF) specimen had the PR of 91.8% (95% CI: 79.9%‐103.7%), followed by rectal swabs; 87.8% (95% CI: 78.6%‐96.9%) then sputum; 68.1% (95% CI: 56.9%‐79.4%). A low PR was observed in oropharyngeal swabs; 7.6% (95% CI: 5.7%‐9.6%) and blood samples; 1.0% (95% CI: −0.1%‐2.1%) whereas no SARS‐CoV‐2 was detected in urine samples. Feces had a PR of 32.8% (95% CI:1 5.8%‐49.8%). Nasopharyngeal swab, a widely used specimen had a PR of 45.5% (95% CI: 31.2%‐59.7%). In this study, SARS‐CoV‐2 was highly detected in LRT specimens while no virus was detected in urinogenital specimens. BLF had the highest PR followed by rectal swab then sputum. Nasopharyngeal swab which is widely used had moderate PR. Low PR was recorded in oropharyngeal swab and blood samples while no virus was found in urine samples. Last, the virus was detected in feces, suggesting SARS‐CoV‐2 transmission by the fecal route.
On Thursday, 30 January 2020, World Health Organization declared Coronavirus disease-2019 (COVID-2019) a Public Health Emergency of International Concern. Since its identification in late December ...2019 in Wuhan, Hubei Province, People's Republic of China, the number of cases imported into other countries is increasing, and the epidemiological map is changing rapidly. On the other hand, body temperature screening (fever) is the major test performed at points of entry, i.e., airports, in the returning travelers in most of the countries with limited resources. However, the recent report on asymptomatic contact transmission of COVID-19 and travelers who passed the symptoms-based screening and tested positive for COVID-19 using reverse transcription polymerase chain reaction (RT-PCR) challenges this approach as body temperature screening may miss travelers incubating the disease or travelers concealing fever during travel. On this note, travel restrictions to and from high risk areas and/or 14 days quarantine of travelers coming from high risk areas are recommended to prevent possible importation of COVID-19. Currently, RT-PCR is a reliable test in detecting both symptomatic and asymptomatic COVID-19.
Current evidence suggests that coronavirus disease 2019 (COVID‐19), caused by severe respiratory syndrome coronavirus 2 (SARS‐CoV‐2), is predominantly transmitted from human‐to‐human. However, ...evidence on vertical transmission and natural passive immunity among the newborns exposed to COVID‐19 is scanty and varies. This poses a challenge on preventive interventions for the newborns. We conducted a systematic review to first, determine the likelihood of vertical transmission among COVID‐19 exposed infants and second, determine whether antibodies against SARS‐CoV‐2 were generated among COVID‐19 vertically exposed but negative infants. This review registered in PROSPERO searched evidence from PubMed/MEDLINE and Google Scholar, among others. About 517 studies were pooled, where 33 articles (5.8%) met the inclusion criteria such as infection prevention and control measures at birth. A total of 205 infants born to COVID‐19 positive mothers were studied. Overall, 6.3% (13/205; 95% CI: 3.0%–9.7%) of the infants tested positive for COVID‐19 virus at birth. Of 33 eligible studies, six studies (18.8%) reported about immunoglobulin G/M (IgG/IgM) against SARS‐CoV‐2. IgG/IgM were detected in 90% infants (10/11; 95% CI: 73.9%–107.9%) who tested negative for COVID‐19 virus. The median antibody levels detected were 75.49 AU/ml (range, 7.25–140.32 AU/ml) and 3.79 AU/ml (range, 0.16–45.83 AU/ml), p = .0041 for IgG and IgM, respectively. In conclusion, the current evidence revealed a low possibility of vertical transmission of COVID‐19 and antibodies against SARS‐CoV‐2 were detected among vertically exposed but negative infants. Further studies on transplacental transmission and the magnitude of natural passive immunity in infants born to mothers with COVID‐19 are warranted.
Highlights
A systematic review was conducted to determine the likelihood of vertical transmission among COVID‐19 exposed infants and whether antibodies against SARS‐CoV‐2 were generated among COVID‐19 vertically exposed but negative infants. We found a low possibility of vertical transmission of COVID‐19 while antibodies against SARS‐CoV‐2 were detected among vertically exposed but negative infants. Further studies on vertical transmission and antibodies against COVID‐19 are warranted.
In Tanzania, chloroquine was replaced by sulphadoxine- pyrimethamine (SP) as a first-line for treatment of uncomplicated malaria. Due to high resistance in malaria parasites, SP lasted for only 5 ...years and by the end of 2006 it was replaced with the current artemisinin combination therapy. We therefore, set a study to determine the current genotypic mutations associated with Plasmodium falciparum resistance to artemisinin, partner drugs and chloroquine. Parasites DNA were extracted from dried blood spots collected by finger-prick from Tanzanian malaria infected patients. DNA were sequenced using MiSeq then genotypes were translated into drug resistance haplotypes at Wellcome Sanger Institute, UK. About 422 samples were successful sequenced for K13 gene (marker for artemisinin resistance), the wild type (WT) was found in 391 samples (92.7%) whereby 31 samples (7.3%) had mutations in K13 gene. Of 31 samples with mutations, one sample had R561H, a mutation that has been associated with delayed parasite clearance in Southeast Asia, another sample had A578S, a mutation not associated with artemisinin whilst 29 samples had K13 novel mutations. There were no mutations in PGB, EXO, P23_BP and PfMDR1 at position 86 and 1246 (markers for resistance in artemisinin partner drugs) but 270 samples (60.4%) had mutations at PfMDR1 Y184F. Additionally, genotyped PfCRT at positions 72-76 (major predictors for chroquine resistance), found WT gene in 443 out of 444 samples (99.8%). In conclusion, this study found mutations in K13-propeller gene and high prevalence of chloroquine susceptible P. falciparum in Southeast of Tanzania.
Cerebrospinal fluid (CSF) viral escape rarely occurs when HIV is detected in the CSF, while it is undetectable in the blood plasma or detectable in CSF at levels that exceed those in the blood ...plasma. We conducted this review to comprehensively synthesise its clinical presentation, diagnosis, management strategies and treatment outcomes. A review registered with PROSPERO (CRD42023475311) searched evidence across PubMed/MEDLINE, Embase, Web of Science, Scopus, and Google Scholar to gather articles (case reports/series) that report on CSF viral escape in people living with HIV (PLHIV) on antiretroviral therapy (ART). The quality of studies was assessed based on the domains of selection, ascertainment, causality, and reporting. A systematic search identified 493 articles and 27 studies that include 21 case reports, and six case series were involved in the review. The studies reported 62 cases of CSF viral escape in PLHIV. The majority were men (66.67%), with a median age of 43 (range: 28–73) years. Approximately, 31 distinct symptoms were documented, mostly being cognitive dysfunction, gait abnormalities, and tremors (12.51%). Diagnosis involved blood and CSF analysis, magnetic resonance imaging, and neuropsychological assessments. Over 36 ART regimens were employed, with a focus on ART intensification; almost one‐third of the regimens contained Raltegravir (integrase strand transfer inhibitor). The outcomes showed 64.49% full recovery, 30.16% partial recovery, and 4.76% died. When neuropsychological symptoms manifest in PLHIV, monitoring for CSF viral escape is essential, regardless of plasma viral suppression. Personalised treatment strategies, particularly ART intensification, are strongly advised for optimising treatment outcomes in PLHIV diagnosed with CSF HIV escape.
Plasmodium falciparum dihydrofolate reductase (Pfdhfr) and dihydropteroate synthetase (Pfdhps) mutations compromise the effectiveness of sulfadoxine-pyrimethamine (SP) for treatment of uncomplicated ...malaria, and are likely to impair the efficiency of intermittent preventive treatment during pregnancy (IPTp). This study was conducted to determine the level of Pfdhfr-Pfdhps mutations, a decade since SP was limited for IPTp use in pregnant women in Tanzania. P. falciparum genomic DNA was extracted from dried blood spots prepared from a finger prick. Extracted DNA were sequenced using a single MiSeq lane by combining all PCR products. Genotyping of Pfdhfr and Pfdhps mutations were done using bcftools whereas custom scripts were used to filter and translate genotypes into SP resistance haplotypes. The Pfdhfr was analyzed from 445 samples, the wild type (WT) Pfdhfr haplotype NCSI was detected in 6 (1.3%) samples. Triple PfdhfrIRNI (mutations are bolded and underlined) haplotype was dominant, contributing to 84% (number n = 374) of haplotypes while 446 samples were studied for Pfdhps, WT for Pfdhps (SAKAA) was found in 6.7% (n = 30) in samples. Double Pfdhps haplotype (SGEAA) accounted for 83% of all mutations at Pfdhps gene. Of 447 Pfdhfr-Pfdhps combined genotypes, only 0.9% (n = 4) samples contained WT gene (SAKAA-NCSI). Quintuple (five) mutations, SGEAA-IRNI accounted for 71.4% (n = 319) whereas 0.2% (n = 1) had septuple (seven) mutations (AGKGS-IRNI). The overall prevalence of Pfdhfr K540E was 90.4% (n = 396) while Pfdhps A581G was 1.1% (n = 5). This study found high prevalence of Pfdhfr-Pfdhps quintuple and presence of septuple mutations. Mutations at Pfdhfr K540E and Pfdhps A581G, major predictors for IPTp-SP failure were within the recommended WHO range. Abandonment of IPTp-SP is recommended in settings where the Pfdhfr K540E prevalence is > 95% and Pfdhps A581G is > 10% as SP is likely to be not effective. Nonetheless, saturation in Pfdhfr and Pfdhps haplotypes is alarming, a search for alternative antimalarial drug for IPTp in the study area is recommended.
Brucellosis is a zoonotic disease transmitted to humans through contact with infected animals, animal products or consumption of infected dairy products. Brucella infection during pregnancy is of ...special interest due to association with adverse pregnancy outcomes. This study determined the seroprevalence and factors associated with Brucella infection among pregnant women around the human-wildlife-livestock interface area in Ngorongoro ecosystem, Northern Tanzania.
A facility-based cross-sectional study was conducted between May and June 2018 at six health facilities that provide antenatal services. Pregnant women receiving antenatal care were invited to participate. A structured questionnaire was used to collect socio-demographic and obstetric characteristics in addition to behavior and practices related to the occurrence of human brucellosis. The presence of serum immunoglobulin against Brucella was determined using Rose Bengal Plate Test (RBPT). The positive samples were further assayed for the presence of IgG and IgM using The enzyme-linkedimmunosorbent assay. Bivariate analysis was conducted to determine the variables associated with Brucella seropositivity. Multivariable logistic regression analysis was performed to examine the factors independently associations with Brucella seropositivity after adjustment for other explanatory variables.
A total of 313 participants were enrolled in the study. The overall seroprevalence of Brucella infection was 10.9% (34/313) determined by Rose Bengal plate test. Of 34 positive individuals, 27(79.4%) and 8(23.5%) were positive in the ELISA specific for IgG and IgM Brucella antibodies respectively. Regular contact with manure (AOR 3.16, 95%CI 1.27-7.83) and preference for animal fresh milk (AOR 3.80, 95% CI 1.23-11.69), raw meat (AOR 2.58, 95% CI 1.14-5.81) and raw animal blood (AOR 2.71, 95% CI 1.15-6.35) increased the odds of being Brucella seropositive. Contact with the animal placenta were not associated with Brucella seropositivity after adjustment.
This study has found that brucellosis is an important public health problem among pregnant women in areas with interactions of humans; livestock and wildlife. The risk of infection increased with the regular contact with manure and preference of raw foodstuffs like animal blood, meat, and milk. We emphasize the need for interventional strategies to reduce the risk of exposure.
To curb HIV infection rate in Tanzania, antiretroviral therapy (ART) has been scaled up since 2006, and in 2019, the country shifted to regimen including dolutegravir as a default first line. We ...assessed the success of ART and the contribution of HIV drug resistance (HIVDR) to unsuppressed viral loads. Between February and May 2023 a cross-sectional survey with random sampling was conducted in the six clinics in an urban cohort in Dar es Salaam. Patients with unsuppresed viral loads (local criteria viral load (VL) ≥ 1000 copies/mL) were tested for HIVDR mutations using the WHO adapted protocol for plasma samples. Mutations were interpreted using the Stanford HIVDR database. In total 600 individuals participated in this survey, the majority were female (76.83%), mean age (Formula: see text standard deviation) was 44.0 (Formula: see text 11.6) years. The median duration on ART (interquartile range) was 6.5 (3.9-10.2) years. Approximately 99% were receiving tenofovir + lamivudine + dolutegravir as a fixed dose combination. VL testing was successful in 99.67% (598/600) of survey patients and only 33 had VL ≥ 1000 copies/mL, resulting in a viral suppression level of 94.48% (565/598, 95% CI 92.34-96.17%). For 23 samples, protease and reverse transcriptase (RT) genotyping were successful, with 13 sequences containing RT inhibitor surveillance drug resistance mutations (SDRMs) (56.5%). No SDRM against protease inhibitors were detected. Thirty samples were successfully genotyped for integrase with 3 sequences (10.08%) containing integrase strand transfer inhibitor (INSTI) SDRMs. In samples successfully genotyped in the three genetic regions, 68.18% (16/22) had a genotypic susceptibility score (GSS) ≥ 2.5 for the concurrent regimen, implying factors beyond drug resistance caused the unsuppressed viral load. For five patients, GSS indicated that HIVDR may have caused the unsuppressed viral load. All three patients with INSTI resistance mutations were highly resistant to dolutegravir and accumulated nucleoside and non-nucleoside RT inhibitor HIVDR mutations. Although in this cohort the last 95 UNAIDS target was almost achieved, HIVDR mutations, including INSTIs resistance mutations were detected in HIV-positive individuals taking ART for at least one year. We recommend the design and implementation of high-impact interventions to prevent the increase of HIVDR, failure of dolutegravir and address the non-resistance factors in the study area.
Jaundice is common among neonates and if untreated can lead to kernicterus. Diagnosing neonatal jaundice (NJ) using Kramer's method (visual assessment) is considered user-friendly in resource-limited ...areas. However, there are conflicting findings on reliability of the Kramer's method in the diagnosis of NJ, particularly of black descent. Therefore, study aimed to determine the accuracy of Kramer's method in comparison to the total serum bilirubin (TSB) test in the diagnosis of NJ among neonates of black descent in Tanzania.
A cross-sectional study was conducted between June and July 2020 at Muhimbili National Hospital (MNH) in Dar es Salaam Tanzania. A total of 315 neonates were recruited consecutively. In each neonate, jaundice was assessed using Kramer's method and TSB test. NJ A total of 315 neonates were recruited i. A 2 X 2 table was created for the determination of sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), positive and negative likelihood ratios (+LR/-LR), and diagnostic accuracy (effectiveness) of Kramer's method. Cohen kappa (κ) was used to analyze the agreement between Kramer's method and TSB. Association between independent variables and presence of jaundice were assessed using the chi-square test and the p < 0.05 was considered to be statistically significant.
The prevalence of NJ was 49.8% by Kramer's method and 63.5% by TSB. The Sensitivity, Specificity, PPV, and NPV of Kramer's method were 70.5, 86.1, 89.8, and 62.6%, respectively. The +LR and -LR were 5.07 and 0.34, respectively. The diagnostic accuracy of Kramer's method was 76.1%. There was a moderate agreement between Kramer's method and TSB results (κ = 0.524, P<0.001). No significant relationship was observed between the independent variables and the presence of NJ.
Kramer has a good positive predictive value. However, due to low sensitivity and NPV one cannot say that overall predictive ability is good. Also, clinical assessment by Kramer's method should not be used for screening of NJ. Further studies are needed to investigate the utility of other non-invasive techniques in detecting NJ among neonates of black descent.
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