The observed prevalence of PID was 0.81/100,000 inhabitants, suggesting considerable underdiagnosis and a need to increase awareness of these conditions in Morocco. The distribution of PIDs was different from that reported in Western countries, with a particularly high proportion of SCID, MHC II deficiencies, hyper-IgE syndrome and autosomal recessive agammaglobulinemia. However, we have now organized a national network, which should improve diagnosis rates in remote regions.

The novel Coronavirus disease 2019 continues to be a worldwide pandemic. Yet, little is still known about the biological features of this emergent infection in children. In this prospective study, we collected 68 children infected with SARS-COV-2 from March 2020 to May 2020, in Marrakesh, Morocco. No severe cases were observed in this cohort, and 66% of the patients were asymptomatic. The main laboratory abnormalities were hematological, as we found Leucopoenia in 4.4% of the cases, hyperleukocytosis in 1.6%. Neutropenia was found in 5 patients (7%) and only 2 cases (3%) had Lymphopenia. The inflammation and coagulation biomarkers were normal in the majority of the cases, as for liver and kidney function. Lactate dehydrogenase (LDH) serum levels were elevated in 8 cases (11.67%). The COVID-19 in children seems to have mild course and better outcome than in adults, which impacts the laboratory findings in this category. More studies must be conducted to learn more about the laboratory abnormalities in pediatric COVID-19.

Ataxia-telangiectasia (AT) is a rare autosomal recessive disease, affecting neurologic and immune system. Numerous mutations are described in the ATM gene in several populations. However, in Morocco, few data are available concerning this condition. Our main goal is to determine clinical, immunological, and molecular presentation of Moroccan patients with AT. We screened 27 patients, out of 22 unrelated families, for ATM gene mutations. All our patients showed ataxia, ocular telangiectasia, and immunodeficiency, as well as elevated serum alphafetoprotein levels. Mean age at diagnosis was 5.51 years, and consanguinity rate was 81.8 %. Mean age at onset was 2.02 years, and mean time to diagnosis was 3.68 years. We found 14 different mutations in 19 unrelated families, of which 7 were not reported. Our results showed that c.5644C>T mutation was the most common in our series. However, further studies are required to demonstrate a founder effects on ATM gene in Moroccan patients, who showed mutational heterogeneity otherwise. Our data indicate that direct sequencing of coding exons is sufficient for a high detection rate in ATM in Moroccan population.

The rst molecular evidence of a monogenic predisposition to mycobacteria came from the study of Mendelian susceptibility to mycobacterial disease (MSMD). We aimed to study this Mendelian susceptibility to mycobacterial diseases in Moroccan kindreds through clinical, immunological and genetic analysis. MethodsPatients presented with clinical features of MSMD, were recruited into this study. We used whole blood samples from patients and age-matched healthy controls. To measure IL-12 and IFN-γ production, samples were activated by BCG plus recombinant human IFN-γ or recombinant human IL-12. Immunological assessments and genetic analysis were also done for patients and their relatives. ResultsOur study involved 22 cases from 15 unrelated Moroccan kindreds. The average age at diagnosis is 4 years. Fourteen patients (64%) were born to consanguineous parents. All patients were vaccinated with BCG vaccine, twelve of them (55%) developed loco-regional or disseminated BCG infections. The other symptomatic patients had severe tuberculosis and/or recurrent salmonellosis. Genetic mutations were identi ed on the following genes: IL12RB1 in 8 patients, STAT1 in 7 patients, SPPL2A, IFNGR1 and TYK2 in two patients and TBX21 in one patient, with different modes of inheritance. All identi ed mutations/variants altered production or response to IFN-γ or both. ConclusionSevere forms of tuberculosis and complications of BCG vaccination may imply a genetic predisposition present in the Moroccan population. In front of these infections, systematic genetic studies became necessary. BCG vaccination is contraindicated in MSMD patients and should be delayed in newborns siblings until the exclusion of a genetic predisposition to mycobacteria.

Since the outbreak of the COVID-19 pandemic, a significant decrease in non-COVID-19 respiratory illnesses were observed, suggesting that the implementation of measures against COVID-19 affected the transmission of other respiratory pathogens. The aim of this study was to highlight the changes in the epidemiology of respiratory pathogens in children during the COVID-19 pandemic. All children with Severe Acute respiratory illness admitted to the pediatric departments between January 2018 and December 2021 with negative COVID-19 PCR, were enrolled. The detection of respiratory pathogens was made by the Film Array Respiratory Panel. A total of 902 respiratory specimens were tested. A significantly lower positivity rate during the COVID-19 period was found (p = 0.006), especially in infants under 6 months (p = 0.008). There was a substantial absence of detection of Respiratory Syncytial Virus and Influenza A during the winter season following the outbreak of the pandemic (p < 0.05; p = 0.002 respectively). An inter-seasonal resurgence of Respiratory Syncytial Virus was noted. Human Rhinovirus was detected throughout the year, and more prevalent in winter during COVID-19 (p = 0.0002). These changes could be explained by the impact of the implementation of preventive measures related to the COVID-19 pandemic on the transmission of respiratory pathogens in children.