Congenital cytomegalovirus infection in newborns suspected of congenital rubella syndrome in Iran: a cross-sectional study.

BACKGROUND: Following rubella virus control, the most important cause of congenital infections is human cytomegalovirus (HCMV). Congenital CMV (cCMV) may happen both in primary and non-primary maternal infections. The present study aimed to screen cCMV in symptomatic newborns suspected of congenital rubella syndrome (CRS) in Iran. METHODS: Out of 1629 collected infants' serum samples suspected of CRS but negative for rubella IgM, 524 samples were selected regarding cCMV complications. These samples were divided into two age groups: 1- one month and younger, 2- older than 1 month up to one year. Anti-HCMV IgM detection was performed on these serums. Then HCMV IgG avidity assay and HCMV DNA detection were carried out on all samples with positive and borderline results in IgM detection. RESULTS: Herein, 3.67% of symptomatic infants aged one month and younger had positive and borderline HCMV IgM, 12.5% of which had a low avidity index (AI). HCMV IgM detection rate among symptomatic infants older than one month to one year was 14.5%. Identified genotypes in this study were gB-1(63.63%), gB2 (18.18%), and gB3 (18.18%), respectively. CONCLUSIONS: This comprehensive study was performed on serum samples of symptomatic infants clinically suspected of cCMV from all over Iran. There was a good correlation between serology findings and PCR.

Impact of COVID-19 on the changing pattern of human orthopneumovirus (respiratory syncytial virus) infection in Iran.

BACKGROUND: Human orthopneumovirus (HOPV) or respiratory syncytial virus (RSV) is one of the important causes of acute respiratory infections (ARIs) during the cold months of the year worldwide. Many countries have reported an absence of ARIs due to HOPV during the winter of 2020-2021 associated with preventive measures to reduce the spread of SARS-CoV2. However, with the reduction of COVID-19 public health restrictions and the absence of immunity in the community due to the lack of exposure in the previous season, many countries had a delayed HOPV outbreak. Here we reported the impact of COVID-19 on the changing pattern of HOPV infection in Iran. METHODS: Throat and nasopharyngeal swab samples were collected from patients (children and adults) with ARIs and sent to the Iran National Influenza Center. After RNA extraction, Real time RT-PCR was performed for HOPV detection. RESULTS: In 260 samples collected from patients with ARIs in three different groups, which included children in March 2021, pilgrims in July 2022, and outpatients during November and December 2022, no HOPV was detected in any group. CONCLUSIONS: The lack of HOPV activity in Iran during the winter of 2020-2021 and then the resurgence in spring 2022 and again the absence of activity in summer and autumn 2022 was extraordinary in the HOPV epidemiology, and probably due to the implementation of public health non-pharmaceutical interventions to reduce the spread of SARS-CoV2. Although it is not possible to keep such restrictions, similar methods can be taken to control outbreaks caused by respiratory viruses.

How to tackle single target gene positive results of SARS-CoV-2 real-time PCR: A cross-sectional study.

Background and Aims: Real-time reverse-transcriptase polymerase chain reaction (real-time RT-PCR) is the gold standard test for diagnosis of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). However, when the test result is near the detection limit of the assay the possibility of getting false positive or negative results is high. In addition, it might result in single target gene positive (STGP) results which should be interpreted with caution. Methods: This study was performed on 29,962 nasal swabs from July 1 to August 31, 2020. Ct values less than 40 for each or both of N and RdRp genes were recommended to be selected as positive. Positive samples for one gene with the Cts more than 35 were rechecked by adding more templates. Results: The results showed that 1016 (3.39%) samples were positive just for one gene with high Ct values. The results of the second reactions showed that 325 (31.99%) samples were positive for both N and RdRp which were reported positive, 301 (29.65%) were positive only for one gene which were considered as suspicious cases and resampling was suggested for them. Finally, 390 (38.385%) samples were negative for both genes. Conclusion: In conclusion, tracking weak positive results of SARS-CoV-2 real-time RT-PCR revealed that most of the individuals who were STGP clean the infection completely in less than a week which showed they were in the convalescent phase of infection. However, some of them who were in the beginning of infection showed a decrease in Ct value during a week, so they could spread the virus in the society.

SARS-CoV-2 intrahost evolution in immunocompromised patients in comparison with immunocompetent populations after treatment.

Many evidence suggests that long-lasting infection can develop with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). This occurrence has been widely described in immunocompromised individuals. In these patients, ineffective clearance of virus infection provides an opportunity for developing immune escape mutants. This study aimed to characterize SARS-CoV-2 intrahost evolution in five immunocompromised in comparison with five immunocompetent COVID-19 patients during treatment. We performed next-generation sequencing (NGS) on collected two oropharyngeal samples from immunocompromised and immunocompetent COVID-19 patients before and after treatment. In this study, we detected alpha and delta variants of SARS-CoV-2. The most common substitutions in structural proteins in patients with alpha variant were S-ΔY143-144, A570D, D614G and D1118H, and N-R203K and G204R, and in delta variant S-T19R, G142D, E156G, 157-158del, L452R, T478K, D614G, D950N and N-D63G, R203M and D377Y were dominant. The common variations in nonstructural and accessory proteins including nsp3-A488S, P1228L, nsp6-T77A, nsp12-P323L, G671S, nsp13-P77L, NS3-S26L, and NS7a-T120I were detected. Also some infrequent substitutions were seen in immunocompromised and immunocompetent patients. After treatment, nsp12-V166A was emerged as a remdesivir resistance and S-L452M in a patient with common variable immunodeficiency. S-E484Q was detected in a patient with acute lymphoma leukemia. This study showed the possibility of the genetic diversity and development of some new mutations in immunocompromised patients. Therefore, surveillance of these patients to characterize any new variants is necessary.

Genomic surveillance of SARS-CoV-2 strains circulating in Iran during six waves of the pandemic.

Background: SARS-CoV-2 genomic surveillance is necessary for the detection, monitoring, and evaluation of virus variants, which can have increased transmissibility, disease severity, or other adverse effects. We sequenced 330 SARS-CoV-2 genomes during the sixth wave of the COVID pandemic in Iran and compared them with five previous waves, for identifying SARS-CoV-2 variants, the genomic behavior of the virus, and understanding its characteristics. Methods: After viral RNA extraction from clinical samples collected during the COVID-19 pandemic, next generation sequencing was performed using the Nextseq and Nanopore platforms. The sequencing data were analyzed and compared with reference sequences. Results: In Iran during the first wave, V and L clades were detected. The second wave was recognized by G, GH, and GR clades. Circulating clades during the third wave were GH and GR. In the fourth wave, GRY (alpha variant), GK (delta variant), and one GH clade (beta variant) were detected. All viruses in the fifth wave were in GK clade (delta variant). In the sixth wave, Omicron variant (GRA clade) was circulating. Conclusions: Genome sequencing, a key strategy in genomic surveillance systems, helps to detect and monitor the prevalence of SARS-CoV-2 variants, monitor the viral evolution of SARS-CoV-2, identify new variants for disease prevention, control, and treatment, and also provide information for and conduct public health measures in this area. With this system, Iran could be ready for surveillance of other respiratory virus diseases besides influenza and SARS-CoV-2.

Surveillance of endemic coronaviruses during the COVID-19 pandemic in Iran, 2021-2022.

Background: Human coronaviruses (HCoVs) 229E, OC43, HKU1, and NL63 are common viruses that continuously circulate in the human population. Previous studies showed the circulation of HCoVs during the cold months in Iran. We studied the circulation of HCoVs during coronavirus disease 2019 (COVID-19) pandemic to find the impact of pandemic on the circulation of these viruses. Methods: As a cross-sectional survey conducted during 2021 to 2022, of all throat swabs sent to Iran National Influenza Center from patients with severe acute respiratory infection, 590 samples were selected to test for HCoVs using one-step real-time RT-PCR. Results: Overall, 28 out of 590 (4.7%) tested samples were found to be positive for at least one HCoVs. HCoV-OC43 was the most common (14/590 or 2.4%), followed by HCoV-HKU1 (12/590 or 2%) and HCoV-229E (4/590 or 0.6%), while HCoV-NL63 was not detected. HCoVs were detected in patients of all ages and throughout the study period with peaks in the cold months of the year. Conclusions: Our multicenter survey provides insight into the low circulation of HCoVs during the COVID-19 pandemic in Iran in 2021/2022. Hygiene habits and social distancing measures might have important role in decreasing of HCoVs transmission. We believe that surveillance studies are needed to track the pattern of HCoVs distributions and detect changes in the epidemiology of such viruses to set out strategies in order to timely control the future outbreaks of HCoVs throughout the nation.

Comparison of Circulating Variants during the Beginning, Middle and the End of the 4th Wave of COVID-19 in Tehran Province, Iran in 2021.

Background: Whole viral genome sequencing with next generation sequencing (NGS) technique is useful tool for determining the diversity of variants and mutations of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). In this study we have attempted to characterize the mutations and circulating variants of the SARSCoV-2 genome during the 4th wave of COVID-19 pandemic in Tehran, Iran in 2021. Methods: We performed complete genome sequencing of 15 SARS-CoV-2 detected from 15 COVID-19 patients during the 4th wave of COVID-19 pandemic with NGS. Three groups of the patients at the beginning, middle and the end of the 4th wave were compared together. Results: We detected alpha and delta variants during the 4th wave of the pandemic. The results illustrated a dominance of amino acid substitution D614G in spike, and the most frequent mutants were N-R203K, G204R, S235F, nsp12-P323L, nsp6-G106del, G107del and F108del. Conclusion: The detection of the virus mutations is a useful procedure for identifying the virus behavior and its genetic evolution in order to improve the efficacy of the monitoring strategies and therapeutic measures.

Molecular epidemiology of human adenoviruses in children with and without respiratory symptoms: Preliminary findings from a case-control study.

BACKGROUND: Human adenovirus (HAdV) is an important viral agent in children which can lead to severe acute respiratory infection (SARI). Reports on molecular epidemiology of HAdVs in Iran are limited. This case-control study is conducted to compare the HAdV infection rate and molecular epidemiology among two groups of children with and without respiratory symptoms in Tehran, Iran during 2018-2019. METHODS: Nested PCR was performed on 120 oropharyngeal swabs taken from children aged five and younger with SARI who were hospitalized as the case group, and 120 oropharyngeal swabs were collected from children of the same age without respiratory symptoms as the control group. For positive samples Sanger sequencing was done and a phylogenetic tree was drawn afterward. RESULTS: Out of 120 cases, 8 (6.6%) tested positive for eachHAdV types including 6 (75%) HAdV-B7, 1 (12.5%) HAdV-C2, and 1 (12.5%) HAdV-C6. Among the control group, out of 120 samples, 8 (6.6%) were positive comprising 5 (62.5%) HAdV-C5, 2 (25%) HAdV-F41, and 1 (12.5%) HAdV-C6. CONCLUSION: The present study indicated a different viewpoint of HAdV molecular epidemiology in which the genotypes were compared in children with and without respiratory symptoms. HAdV prevalence was equally common in cases and controls but different genotypes were detected in these two groups. HAdV-B7 was the main type among children with SARI, dissimilar to children with no respiratory symptoms where HAdV-C5 was the predominant type. Detecting HAdV-F in oropharyngeal swabs was a rare finding, which requires further investigation.

Potential role of viral infections in miscarriage and insights into the underlying molecular mechanisms.

Intrauterine viruses can infect the decidua and placenta and cause adverse effects on the fetus during gestation. This review discusses the contribution of various viral infections to miscarriage and the molecular mechanisms by which viruses can cause devastating effects on healthy fetuses and induce miscarriage. Severe acute respiratory syndrome coronavirus 2 as newly emerged coronavirus was considered here, due to the concerns about its role during pregnancy and inducing miscarriage, as well. In this narrative review, an extensive literature search was conducted to find all studies investigating viral infections in miscarriage and their molecular mechanisms published over the past 20 years. The results of various studies investigating the roles of 20 viral infections in miscarriage are presented. Then, the mechanisms of pregnancy loss in viral infections were addressed, including alteration of trophoblast invasion and placental dysfunction, inducing excessive maternal immune response, and inducing apoptosis in the placental tissue. Viruses may cause pregnancy loss through different mechanisms and our knowledge about these mechanisms can be helpful for controlling or preventing viral infections and achieving a successful pregnancy.

Mucormycosis infection in severe COVID-19 patient with multiple underlying health conditions.

Patients with underlying health conditions are vulnerable to invasive fungal infection following COVID-19. It seems that uncontrolled diabetes mellitus makes patients susceptible to both severe COVID-19 and mucormycosis.

SARS-CoV-2: an imperative maternal-fetal concern.

Severe acute respiratory syndrome corona virus 2 (SARS-CoV-2) is a newly emerged virus which belongs to Coronaviridae family within the betacoronavirus genus. Previous reports demonstrated that other betacoronaviruses were responsible for adverse outcomes during pregnancy in human. Due to inadequate data, the consequences of a SARS-CoV-2 infection during pregnancy is still a public health concern in the second year of SARS-CoV-2 circulation in human population. Herein, we aimed to review the probable risk of intrauterine vertical transmission of SARS-CoV-2 infection to the fetus, its adverse outcomes during pregnancy for both mother and the fetus and maternal risk factors which affect the severity Coronavirus disease 2019 (COVID-19.