Covid-19 related isolation and risk of post-traumatic stress disorder in patients presenting to tele-clinics at a private tertiary care hospital in Karachi.

The objective of this study was to assess the psychological impact of isolation on individuals with Covid-19 and determine the experiences of people in isolation. All adults with Covid-19 who reported to the infectious disease tele-clinic were included in the study; participants were sent the survey form via email. The email was sent to 146 people and 47 responses were received. IES-R questionnaire was submitted to all individuals on Day 7 of quarantine, along with a qualitative questionnaire. The mean score on IES-R for all the respondents was 18.77. Out of 47 participants, for 6 (12.8%) PTSD was a clinical concern, 3 (6.4%) participants had a probable diagnosis of PTSD, and 6 (12.8%) participants scored high enough to suppress immune function. The majority of participants reported stress due to confinement in an isolated space and interruption in daily routine, specifically work-related routine. Praying, meditation, and having social support helped the participants cope with the isolation.

Impact of Postoperative Antibiotic Prophylaxis on Surgical Site Infections Rates After Mastectomy with Drains but Without Immediate Reconstruction: A Multicenter, Double-Blinded, Randomized Control Superiority Trial.

BACKGROUND: There is no consensus on the use of postoperative antibiotic prophylaxis (PAP) after mastectomy with indwelling drains. We explored the utility of continued PAP in reducing surgical site infection (SSI) rates after mastectomy without immediate reconstruction and with indwelling drains. PATIENTS AND METHODS: A multicenter, two-armed, randomized control superiority trial was conducted in Pakistan. We enrolled all consenting adult patients undergoing mastectomy without immediate reconstruction. All patients received a single preoperative dose of cephalexin within 60 min of incision, and postoperatively were randomized to receive either continued PAP using cephalexin (intervention) or a placebo (control) for the duration of indwelling, closed-suction drains. The primary outcome was the development of SSI within 30 days and 90 days postoperatively. Secondary outcomes included study-drug-associated adverse events. Intention-to-treat analysis was performed using multivariable Cox regression. RESULTS: A total of 369 patients, 180 (48.8%) in the intervention group and 189 (51.2%) in the control group, were included in the final analysis. Overall cumulative SSI rates were 3.5% at 30 days and 4.6% at 90 days postoperatively. PAP was not associated with SSI reduction at 30 (hazard ratio, HR 1.666 [95% confidence interval CI 0.515-5.385]) or 90 (1.575 [0.558-4.448]) days postoperatively, or with study-drug-associated adverse effects (0.529 [0.196-1.428]). CONCLUSIONS: Continuing antibiotic prophylaxis for the duration of indwelling drains after mastectomy without immediate reconstruction offers no additional benefit in terms of SSI reduction. There is a need to update existing guidelines to provide clearer recommendations regarding use of postoperative antibiotic prophylaxis after mastectomy in the setting of indwelling drains.

Humoral and T cell responses to SARS-CoV-2 reveal insights into immunity during the early pandemic period in Pakistan.

BACKGROUND: Protection against SARS-CoV-2 is mediated by humoral and T cell responses. Pakistan faced relatively low morbidity and mortality from COVID-19 through the pandemic. To examine the role of prior immunity in the population, we studied IgG antibody response levels, virus neutralizing activity and T cell reactivity to Spike protein in a healthy control group (HG) as compared with COVID-19 cases and individuals from the pre-pandemic period (PP). METHODS: HG and COVID-19 participants were recruited between October 2020 and May 2021. Pre-pandemic sera was collected before 2018. IgG antibodies against Spike and its Receptor Binding Domain (RBD) were determined by ELISA. Virus neutralization activity was determined using a PCR-based micro-neutralization assay. T cell - IFN-γ activation was assessed by ELISpot. RESULTS: Overall, the magnitude of anti-Spike IgG antibody levels as well as seropositivity was greatest in COVID-19 cases (90%) as compared with HG (39.8%) and PP (12.2%). During the study period, Pakistan experienced three COVID-19 waves. We observed that IgG seropositivity to Spike in HG increased from 10.3 to 83.5% during the study, whilst seropositivity to RBD increased from 7.5 to 33.3%. IgG antibodies to Spike and RBD were correlated positively in all three study groups. Virus neutralizing activity was identified in sera of COVID-19, HG and PP. Spike reactive T cells were present in COVID-19, HG and PP groups. Individuals with reactive T cells included those with and without IgG antibodies to Spike. CONCLUSIONS: Antibody and T cell responses to Spike protein in individuals from the pre-pandemic period suggest prior immunity against SARS-CoV-2, most likely from cross-reactive responses. The rising seroprevalence observed in healthy individuals through the pandemic without known COVID-19 may be due to the activation of adaptive immunity from cross-reactive memory B and T cells. This may explain the more favourable COVID-19 outcomes observed in this population.

Comparison of risk factors and outcome of patients with and without COVID-19-associated pulmonary aspergillosis from Pakistan: A case-control study.

BACKGROUND: Early identification of COVID-19-associated pulmonary aspergillosis (CAPA) is particularly challenging in low- middle-income countries where diagnostic capabilities are limited, and risk factors for CAPA have not been identified. It is also essential to recognise CAPA patients who are likely to have a poorer outcome to decide on aggressive management approaches. Therefore, this study aimed to identify risk factors and outcomes for CAPA among admitted moderate to critical COVID-19 patients at our centre in Pakistan. METHODS: An unmatched case-control study with ratio of 1:2 was conducted on hospitalised adult patients with COVID-19 from March 2020-July 2021. Cases were defined according to European Confederation of Medical Mycology and the International Society for Human and Animal Mycology consensus criteria. Controls were defined as patients hospitalised with moderate, severe or critical COVID-19 without CAPA. RESULTS: A total of 100 CAPA cases (27 probable CAPA; 73 possible CAPA) were compared with 237 controls. Critical disease at presentation (aOR 5.04; 95% CI 2.18-11.63), age ≥ 60 years (aOR 2.00; 95% CI 1.20-3.35) and underlying co-morbid of chronic kidney disease (CKD) (aOR 3.78; 95% CI 1.57-9.08) were identified as risk factors for CAPA. Patients with CAPA had a significantly greater proportion of complications and longer length of hospital stay (p-value < .001). Mortality was higher in patients with CAPA (48%) as compared to those without CAPA (13.5%) [OR = 6.36(95% CI 3.6-11)]. CONCLUSIONS: CAPA was significantly associated with advanced age, CKD and critical illness at presentation, along with a greater frequency of complications and higher mortality.

Comparison of risk factors and outcomes of Candida auris candidemia with non-Candida auris candidemia: A retrospective study from Pakistan.

Candida auris has emerged as a nosocomial multi-drug resistant pathogen. This study aimed to compare the risk factors and outcomes of C. auris candidemia patients with non-C. auris candidemia, at a single center in Pakistan. A retrospective study compared 38 C. auris with 101 non-C. auris (36 C. albicans, 38 C. tropicalis, and 27 C. parapsilosis) candidemia patients between September 2014 and March 2017 at the Aga Khan University Hospital, Pakistan. Demographics, clinical history, management and outcomes were studied. Prior history of surgery (adjusted odds ratio [aOR] 4.9, 95% confidence interval [CI]: 1.4-17.5), antifungals exposure (aOR 38.3, 95% CI: 4.1-356) and prior MDR bacteria isolation (aOR 5.09, 95% CI: 1.6-15.9) were associated with C. auris candidemia. On survival analysis both groups of patients had similar outcome in terms of mortality (62.6% vs. 52.54%, hazard ratio [HR] 1.45, 95% CI: 0.84-2.4, P-value = .17) and microbiological failure rates (42.3% vs. 32.2%, HR 0.65, 95% CI: 0.35-1.2, P-value = .17) however, C. auris patients had a higher mean hospital stay (36.32 days vs. 14.8 days, P-value = <.001) and higher >15-day in-hospital stay from positive culture (HR 2.68, 95% CI: 1.1-6.3, P-value = .025). Antifungal susceptibility was different, with C. auris more often resistant to voriconazole (29.6% vs. 0%) and amphotericin (3.7 vs. 0%); though no echinocandin resistance was detected in either group. As opposed to other Candida species, C. auris candidemia occurred after nosocomial exposure, and its source was most commonly an indwelling line. Although these patients had a higher in-hospital stay, but there was no excess mortality when compared to other Candida species.

The emergence of an unassigned complex recombinant form in a Pakistani HIV-infected individual.

In Pakistan, the HIV situation has gone from an outbreak to a concentrated epidemic, and the virus has now crossed into the low-risk population. In addition, several new HIV outbreaks have occurred in different parts of the country. HIV-1 subtype A has been the major epidemic subtype in Pakistan; however, as the epidemic has grown, the emergence of several new subtypes and recombinant forms has been observed. Here, we present the first case and genetic analysis of an unassigned, complex recombinant form in a Pakistani HIV-infected individual with virological failure. Genetic analysis of the sequence indicated that this recombinant form is multi-drug resistant, harboring drug resistance mutations against more than one class of antiretroviral drugs.

COVID-19-associated pulmonary aspergillosis (CAPA) in patients admitted with severe COVID-19 pneumonia: An observational study from Pakistan.

BACKGROUND: Invasive aspergillosis is a well-known complication of severe influenza pneumonia with acute respiratory distress syndrome (ARDS). However, recent studies are reporting emergence of aspergillosis in severe COVID-19 pneumonia, named as COVID-19-associated pulmonary aspergillosis (CAPA). METHODS: A retrospective observational study was conducted in patients with severe COVID-19 pneumonia from February 2020 to April 2020. Patients ≥18 years of age with clinical features and abnormal chest imaging with confirmed COVID-19 by RT-PCR for SARS-CoV-2 were included. CAPA was diagnosed based on clinical parameters, radiological findings and mycological data. Data were recorded on a structured proforma, and descriptive analysis was performed using Stata ver 12.1. RESULTS: A total of 147 patients with confirmed COVID-19 and 23 (15.6%) patients requiring ICU admission were identified. Aspergillus species were isolated from tracheal aspirates of nine (39.1%) patients, and of these, five patients (21.7%) were diagnosed with CAPA and four (17.4%) had Aspergillus colonisation. The mean age of patients with CAPA was 69 years (Median age: 71, IQR: 24, Range: 51-85), and 3/5 patients were male. The most frequent co-morbid was diabetes mellitus (4/5). The overall fatality rate of COVID-19 patients with aspergillosis was 44% (4/9). The cause of death was ARDS in all three patients with CAPA, and the median length of stay was 16 days (IQR: 10; Range 6-35 days). CONCLUSION: This study highlights the need for comparative studies to establish whether there is an association of aspergillosis and COVID-19 and the need for screening for fungal infections in severe COVID-19 patients with certain risk factors.

Clinical spectrum and factors impacting outcome of Candida auris: a single center study from Pakistan.

BACKGROUND: An outbreak of Candida auris began globally in 2014 including Pakistan and since then it has emerged as a nosocomial multi-drug resistant pathogen. The aim of this study was to assess the clinical spectrum and outcome of patients, from a single center in Pakistan, in whom C. auris was isolated. METHODS: A retrospective study was conducted on 92 patients; ≥16 years with at least one culture positive for C. auris, at the Aga Khan University Hospital Karachi, Pakistan from Sept 2014-Mar 2017.Demographics, clinical history, management and outcome were studied. A logistic regression model was used to identify the risk factors for mortality. RESULTS: We identified 92 patients with C. auris (193 isolates), of whom 52.2% were males. Mean age was 54.14 ± 20.4 years. Positive cultures were obtained after a median hospital stay of 14 days. Most patients had a history of surgery (57.6%), antibiotic use (95.6%), ICU stay (44.6%), indwelling lines (88.04%) and isolation of another multi-resistant organism (52.2%).Most patients were symptomatic (70.7%). Amongst these, 38 had candidemia while 27 had non-candidemia infections. Sites of infection included central lines (35), urinary tract (19), peritonitis (4), nosocomial ventriculitis (1), empyema (1), fungal keratitis (1) otitis externa (1) and surgical site (1). Fluconazole resistance was 100% while 28.5 and 7.9% were Voriconazole and Amphotericin resistant respectively. Overall crude mortality was 42.4% while 14-day mortality was 31.5%. Both infected and colonized cases shared similar mortality (46.2% vs 33.3%; p-value = 0.25). Among infected cases mortality was high in candidemia compared to non-candidemia (60.5% vs 25.9%) in which deaths related to C. auris were 34.2% vs 22.2% respectively. On multivariate analysis candidemia (AOR 4.2, 95% CI: 1.09-16.49; p-value = 0.037) was associated with greater mortality with source control being the only protective factor for mortality (AOR 0.22, 95% CI: 0.05-0.92; p-value0.038] while ICU stay, rapidity of blood culture clearance, DM, malignancy and MDR co-infection had no impact. CONCLUSION: Patients with C.auris from a single center in Pakistan have a wide clinical spectrum with line associated infection being the predominant site of infection. Candidemia leads to high mortality while source control improves outcome.

Hypermucoviscous Klebsiella syndrome it's in the community!

Hypermucoviscous Klebsiella syndrome is a unique syndrome caused by a new variant of Klebsiella pneumoniae (KP), characterized by abscess formation at distant body sites. This emerging KP strain is different from the usual classic strains in having the rmp gene which increases capsule formation making this strain resistant to phagocytosis and helping in its dissemination to distant organs. A 50 years old diabetic man presented with facial swelling after dental procedure which progressively increased despite being on antibiotics. On examination he was febrile, had neck swelling with signs of inflammation and tender hepatomegaly. Ultrasonography showed submental and liver abscesses which were subsequently drained and both cultures isolated KP with hypermucoid colonies on agar plate and a positive string test indicating the presence of this new hypervirulent strain of KP. Therefore, a diagnosis of Hypermucoviscous Klebsiella syndrome should be considered in all patients who present with KP infection with multiple organ abscesses..

Mortality In Patients With Respiratory And Nonrespiratory Carbapenem Resistant-Multidrug Resistant Acinetobacter Infections.

BACKGROUND: Mortality from carbapenem-multi-drug resistant Acinetobacter infections may vary according to site of infection. The objective of this study was to compare mortality in respiratory vs. non-respiratory infection with Carbapenem-Multi-drug Resistant Acinetobacter (C-MRAB). METHODS: We conducted a prospective cohort study to compare mortality rate in patients with respiratory vs. nonrespiratory infection (n=30 each). RESULTS: Results showed that mortality was 40% in the respiratory group compared to 23% in non-respiratory group; the difference was not statistically significant (p=0.165, RR=1.71, CI=0.73-3.75). There was a significantly higher prior admission rate in patients with respiratory infection (p=0.028). Logistic regression did not reveal any modifier effect from other variables. CONCLUSIONS: This study showed no significant difference in mortality in patients with carbapenem-multi-drug resistant acinetobacter respiratory vs. non-respiratory infections.

Comparison of the clinical presentations of Naegleria fowleri primary amoebic meningoencephalitis with pneumococcal meningitis: a case-control study.

BACKGROUND: Primary amoebic meningoencephalitis (PAM) is a rare but fatal infection caused by Naegleria fowleri. The infection is acquired by deep nasal irrigation with infected water. Patients present with signs and symptoms similar to pneumococcal meningitis, leading to delayed diagnosis and treatment and hence high mortality. METHODS: We conducted a case-control study comparing culture proven cases of PAM with pneumococcal meningitis presenting to our center between April 2008 and September 2014. Only patients with blood and/or cerebrospinal fluid cultures positive for Streptococcus pneumoniae during the same time period were included for comparison. RESULTS: There were 19 cases of PAM and pneumococcal meningitis, each. When comparing PAM with pneumococcal meningitis, patients with PAM were more likely to be male (89.5 vs. 36.8 %), younger (mean age: 30 vs. 59 years), present with seizures (42.1 vs. 5.3 %). Both groups of patients presented with similar vital signs and there were no remarkable differences on physical examinations, Glasgow Coma Scale scores, laboratory and radiological investigations and cerebrospinal fluid parameters. PAM was also more likely to present if the city's average maximum temperature was higher in the previous week (mean: 34.6 vs. 30 °C). There was history of fresh water contact in only one patient. On multivariate analysis, PAM was more likely if patients presented when the city's average maximum temperature was high, being young males. CONCLUSION: PAM and pneumococcal meningitis remain virtually indistinguishable; however, these predictive features should be validated in a prospective study and may lead to a viable algorithm for early management of these patients.

Shift in SARS-CoV-2 variants of concern from Delta to Omicron was associated with reduced hospitalizations, increased risk of breakthrough infections but lesser disease severity.

BACKGROUND: COVID-19 epidemiology changed with the emergence of SARS-CoV-2 variants of concern (VOC). Pakistan administered mostly inactivated vaccines. We investigated the association between VOC and breakthrough infections in a mixed-vaccination-status population of Karachi. METHODS: We investigated SARS-CoV-2 VOC tested in 392 respiratory specimens collected between May and December 2021. Data for age, sex, hospital admission, vaccinations, together with CT values of the diagnostic PCR test were analyzed. RESULTS: The median age of COVID-19 cases tested was 40 (27-57) years and 43.4% were female. Delta variants were most common (56.4%) followed by Alpha (15.9%), Omicron (12.2%), Beta/Gamma (11.3%), and others (4.3%). Eighteen percent of cases were hospitalized whereby, predominant VOC were Beta/Gamma (40.8%), Alpha (35.2%) and Delta (22.5%). Overall, 55.4% of individuals were fully vaccinated, 7.4% were partially vaccinated and 37.2% were unvaccinated. Most (74.6%) inpatients were unvaccinated. Vaccines comprised inactivated (85.34%), single-shot vector (8.62%), two-shot vector (3.02%) and mRNA (3.02%) types. Omicron variants showed lower viral loads as compared to Alpha, Beta/Gamma, and Delta (p = 0.017). The risk of infection with Delta and Omicron variants was higher, 8 weeks after vaccination. The majority of those with breakthrough infections after receiving inactivated vaccines acquired COVID-19 within 4 months of vaccination. CONCLUSION: Our data highlights the shifting of VOC from Delta to Omicron during 2021 and that COVID-19 vaccinations reduced both hospitalizations and viral transmission. It informs on the increased risk of breakthrough infection within 8 weeks of vaccination, indicating the need for booster vaccinations.

Human Immunodeficiency Virus Type-1 Genetic Diversity and Drugs Resistance Mutations among People Living with HIV in Karachi, Pakistan.

The human immunodeficiency virus type-1 epidemic in Pakistan has significantly increased over the last two decades. In Karachi, Pakistan, there is a lack of updated information on the complexity of HIV-1 genetic diversity and the burden of drug resistance mutations (DRMs) that can contribute to ART failure and poor treatment outcomes. This study aimed to determine HIV-1 genetic diversity and identify drug-resistance mutations among people living with HIV in Karachi. A total of 364 HIV-positive individuals, with a median age of 36 years, were enrolled in the study. The HIV-1 partial pol gene was successfully sequenced from 268 individuals. The sequences were used to generate phylogenetic trees to determine clade diversity and also to assess the burden of DRMs. Based on the partial pol sequences, 13 distinct HIV-1 subtypes and recombinant forms were identified. Subtype A1 was the most common clade (40%), followed by CRF02_AG (33.2%). Acquired DRMs were found in 30.6% of the ART-experienced patients, of whom 70.7%, 20.7%, and 8.5% were associated with resistance to NNRTIs, NRTIs, and PIs, respectively. Transmitted DRMs were found in 5.6% of the ART-naïve patients, of whom 93% were associated with resistance against NNRTIs and 7% to PIs. The high prevalence of DRMs in ART-experienced patients poses significant challenges to the long-term benefits and sustainability of the ART program. This study emphasizes the importance of continuous HIV molecular epidemiology and drug resistance surveillance to support evidence-based HIV prevention, precise ART, and targeted AIDS care.

Effectiveness of inactivated COVID-19 vaccines against SARS-CoV-2 infections among healthcare personnel in Pakistan: a test-negative case-control study.

OBJECTIVE: During the COVID-19 pandemic, several vaccines that were efficacious in randomised controlled trials were authorised for mass vaccination. In developing countries, inactivated vaccines were widely administered. While inactivated vaccines have been deemed effective in reducing disease severity, for healthcare personnel (HCP), effectiveness against SARS-CoV-2 infections is essential to reduce the risk to vulnerable patients and ensure a stable healthcare workforce. There are limited studies examining inactivated vaccines' effectiveness against SARS-CoV-2 variants of concern (VOCs) in real-world settings. We estimated the effectiveness of inactivated vaccines (BBIBP-CorV and CoronaVac) against reverse transcription PCR (RT-PCR)-confirmed SARS-CoV-2 infections among HCP in the setting of emerging SARS-CoV-2 VOCs in Pakistan. DESIGN: A retrospective matched, test-negative case-control analysis using existing data from an Employee Health database on HCP at a large, private healthcare system in Pakistan. PARTICIPANTS: 4599 HCP were tested between 1 April and 30 September 2021. Each case (PCR positive) was matched to two to six controls (PCR negative) by the date of the RT-PCR test (±7 days) to reduce bias. PRIMARY AND SECONDARY OUTCOME MEASURES: The primary outcome was vaccine effectiveness (VE) against SARS-CoV-2 infection. The secondary outcome was VE against symptomatic SARS-CoV-2 infection. Per cent VE was calculated using (1-OR)*100, with the OR of getting a PCR-confirmed SARS-COV-2 infection estimated using conditional logistic regression, after adjusting for age, gender, work area and history of SARS-CoV-2 infection. RESULTS: Inactivated vaccines were ineffective against SARS-CoV-2 infections after receiving the first dose (VE 17%, 95% CI -10, 39; p=0.261). They showed modest effectiveness ≥14 days after the second dose against SARS-CoV-2 infections (VE 30%, 95% CI 7, 48; p=0.015) and symptomatic SARS-CoV-2 infections (VE 33%, 95% CI 6, 52; p=0.002). CONCLUSIONS: Inactivated vaccines show modest effectiveness against SARS-CoV-2 infections in the setting of emerging VOCs. This builds a strong case for boosters and/or additional vaccination.

Using rapid antigen testing for early, safe return-to-work for healthcare personnel after SARS-CoV-2 infection in a healthcare system in Pakistan: A retrospective cross-sectional study.

Anticipating staff shortage during the Omicron variant surge, we modified the US Centers for Disease Control and Prevention's contingency guidelines at a healthcare system in Pakistan. Infected staff had a SARS-CoV-2 rapid antigen test after 5-7 days of isolation, to decide a safe return-to-work. This led to signifcant cost savings without compromising patient/staff safety.

Exploring the relationship between SARS-CoV-2 variants, illness severity at presentation, in-hospital mortality and COVID-19 vaccination in a low middle-income country: A retrospective cross-sectional study.

Background and Aims: COVID-19 morbidity and mortality varied globally through the pandemic. We studied the relationship of SARS-CoV-2 variants of concern (VOC) with COVID-19 severity and mortality among hospitalized patients in Pakistan. Methods: A retrospective review of clinical, laboratory, and vaccination data of 197 COVID-19 adult patients at the Aga Khan University Hospital, Karachi between April 2021, and February 2022 was performed. SARS-CoV-2 VOC identified in respiratory samples were analyzed. Univariate and multivariate analysis was conducted to identify factors associated with COVID-19 outcomes. Results: The median age of cases was 55 years and 51.8% were males. Twenty-four percent of females were pregnant. Of COVID-19 cases, 48.2% had nonsevere disease, while 52.8% had severe/critical disease. Hypertension (48%) and diabetes mellitus (41%) were common comorbids. SARS-CoV-2 VOC identified comprised; Omicron (55.3%), Beta (14.7%), Alpha (13.7%), Delta (12.7%), and Gamma (3.6%) variants. Most (59.7%) study subjects were unvaccinated. Of vaccines, 88% had received inactivated virus COVID-19 vaccines. Increased risk of severe disease was associated with age ≥50 years (odds ratio [OR]: 5.73; 95% confidence interval [CI]: [2.45-13.7]), as well as with diabetes mellitus (OR: 4.24; 95% CI: [1.82-9.85]). Full vaccination (OR: 0.25; 95% CI: [0.11-0.58]) or infection with Omicron (OR: 0.42; 95% CI: [0.23-0.74]) was associated with reduced disease severity. The risk of mortality increased with age ≥50 years (OR: 5.07; 95% CI: [1.92-13.42]) and a history of myocardial infarction (OR: 5.11; 95% CI: [1.45-17.93]) whilst, infection with Omicron was found to reduce the risk (OR: 0.22; 95% CI: [0.10-0.53]). Conclusion: Our study describes the relationship between the severity of COVID-19, in-hospital mortality in relation to SARS-CoV-2 variants, and the impact of COVID-19 vaccination in Pakistan. Outcomes were more favorable in younger individuals, after vaccinations and with Omicron variant infections. Most cases received inactivated virus vaccines therefore these data highlight the protection provided against severe COVID-19.

Genetic and antiretroviral drug resistance mutations analysis of reverse transcriptase and protease gene from Pakistani people living with HIV-1.

BACKGROUND: Antiretroviral therapy (ART) effectiveness is compromised by the emergence of HIV drug resistance mutations (DRM) and can lead to the failure of ART. Apart from intrinsic viral factors, non-compliance with drugs and/or the use of sub-optimum therapy can lead to the emergence of DRMs. In Pakistan HIV currently exists as a concentrated epidemic, however, ART coverage is very low, and drug adherence is poor. ART is selected assuming without baseline genotyping. Pakistan has recently seen a rise in treatment failures, but the country's actual burden of DRM is still unknown. In this study, we perform the genetic and drug resistance analysis of the pol gene from Pakistani HIV-positive ART-naïve and ART-experienced individuals. METHODS: In this study, HIV-1 pol was sequenced from 146 HIV-1 positive individuals, divided into ART-naïve (n = 37) and ART-experienced (n = 109). The sequences were also used to determine HIV-1 subtypes, the prevalence of DRM, and pol genetic variability. RESULTS: DRM analysis identified numerous DRMs against reverse transcriptase inhibitors in both ART-naïve and ART-experienced groups, including a few that are classified as rare. Additionally, the ART-experienced group showed mutations associated with resistance to protease inhibitors. Genetic analysis showed negative selection pressure in both groups, but a higher rate of evolution in the ART-naïve group. CONCLUSION: High prevalence of DRMs, especially against previous first-line treatment in ART- naïve and the accumulation of DRMs in ART-experienced groups is concerning and warrants that a more extensive DRM survey be carried out to inform first-line and second-line ART regimen recommendations.

Tracking SARS-CoV-2 variants through pandemic waves using RT-PCR testing in low-resource settings.

COVID-19 resulted in extensive morbidity and mortality worldwide. SARS-CoV-2 evolved rapidly, with increasing transmission due to Variants of Concern (VOC). Identifying VOC became important but genome submissions from low-middle income countries (LMIC) remained low leading to gaps in genomic epidemiology. We demonstrate the use of a specific mutation RT-PCR based approach to identify VOC in SARS-CoV-2 positive samples through the pandemic in Pakistan. We selected 2150 SARS-CoV-2 PCR positive respiratory specimens tested between April 2021 and February 2022, at the Aga Khan University Hospital Clinical Laboratories, Karachi, Pakistan. Commercially available RT-PCR assays were used as required for mutations in Spike protein (N501Y, A570D, E484K, K417N, L452R, P681R and deletion69_70) to identify Alpha, Beta, Gamma, Delta, and Omicron variants respectively. Three pandemic waves associated with Alpha, Delta and Omicron occurred during the study period. Of the samples screened, VOC were identified in 81.7% of cases comprising mainly; Delta (37.2%), Alpha (29.8%) and Omicron (17.1%) variants. During 2021, Alpha variants were predominant in April and May; Beta and Gamma variants emerged in May and peaked in June; the Delta variant peaked in July and remained predominant until November. Omicron (BA.1) emerged in December 2021 and remained predominant until February 2022. The CT values of Alpha, Beta, Gamma and Delta were all significantly higher than that of Omicron variants (p<0.0001). We observed VOC through the pandemic waves using spike mutation specific RT-PCR assays. We show the spike mutation specific RT-PCR assay is a rapid, low-cost and adaptable for the identification of VOC as an adjunct approach to NGS to effectively inform the public health response. Further, by associating the VOC with CT values of its diagnostic PCR we gain information regarding the viral load of samples and therefore the level of transmission and disease severity in the population.

Investigating the impact of prior COVID-19 on IgG antibody and interferon γ responses after BBIBP-CorV vaccination in a disease endemic population: A prospective observational study.

Background and Aims: COVID-19 vaccinations have reduced morbidity and mortality from the disease. Antibodies against severe acute respiratory syndrome coronavirus 2 (SARS­CoV­2) have been associated with immune protection. Seroprevalence studies revealed high immunoglobulin G (IgG) antibody levels to SARS-CoV-2 in the Pakistani population before vaccinations. We investigated the effect of BBIBP-CorV vaccination on circulating IgG antibodies and interferon (IFN)-γ from T cells measured in a cohort of healthy individuals, with respect to age, gender, and history of COVID-19. Methods: The study was conducted between April and October 2021. BBIBP-CorV vaccinated participants were followed up to 24 weeks. Antibodies to SARS-CoV-2 Spike protein and its receptor-binding domain (RBD) were measured. IFNγ secreted by whole blood stimulation of Spike protein and extended genome antigens was determined. Results: Study participants with a history of prior COVID-19 displayed a higher magnitude of IgG antibodies to Spike and RBD. IgG seropositivity was greater in those with prior COVID-19, aged 50 years or younger and in females. At 24 weeks after vaccination, 37.4% of participants showed IFN-γ responses to SARS-CoV-2 antigens. T cell IFN-γ release was higher in those with prior COVID-19 and those aged 50 years or less. Highest IFN-γ release was observed to extended genome antigens in individuals both with and without prior COVID-19. Conclusion: We found that IgG seropositivity to both Spike and RBD was affected by prior COVID-19, age and gender. Importantly, seropositive responses persisted up to 24 weeks after vaccination. Persistence of vaccine induced IgG antibodies may be linked to the high seroprevalence observed earlier in unvaccinated individuals. Increased T cell reactivity to Spike and extended genome antigens reflects cellular activation induced by BBIBP-CorV. COVID-19 vaccination may have longer lasting immune responses in populations with a higher seroprevalence. These data inform on vaccination booster policies for high-risk groups.