African histoplasmosis in HIV-negative patients, Kimpese, Democratic Republic of the Congo

We describe a case series of histoplasmosis caused by Histoplasma capsulatum var. duboisii during July 2011–January 2014 in Kimpese, Democratic Republic of the Congo. Cases were confirmed by histopathology, immunohistochemistry, and reverse transcription PCR. All patients were HIV negative. Putative sources for the pathogen were cellar bats and guano fertilizer exploitation

A typical hospital-acquired methicillin-resistant Staphylococcus aureus clone is widespread in the community in the Gaza strip.

Epidemiological data on community acquired methicillin-resistant-Staphylococcus aureus (CA-MRSA) carriage and infection in the Middle-East region is scarce with only few reports in the Israeli and Palestinian populations. As part of a Palestinian-Israeli collaborative research, we have conducted a cross-sectional survey of nasal S. aureus carriage in healthy children and their parents throughout the Gaza strip. Isolates were characterized for antibiotic susceptibility, mec gene presence, PFGE, spa type, SCCmec-type, presence of PVL genes and multi-locus-sequence-type (MLST). S. aureus was carried by 28.4% of the 379 screened children-parents pairs. MRSA was detected in 45% of S. aureus isolates, that is, in 12% of the study population. A single ST22-MRSA-IVa, spa t223, PVL-gene negative strain was detected in 64% of MRSA isolates. This strain is typically susceptible to all non-β-lactam antibiotics tested. The only predictor for MRSA carriage in children was having an MRSA carrier-parent (OR=25.5, P=0.0004). Carriage of the Gaza strain was not associated with prior hospitalization. The Gaza strain was closely related genetically to a local MSSA spa t223 strain and less so to EMRSA15, one of the pandemic hospital-acquired-MRSA clones, scarcely reported in the community. The rapid spread in the community may be due to population determinants or due to yet unknown advantageous features of this particular strain

Distribution of MLSTs among MRSA and MSSA isolates tested.

<p>Black – MRSA, Grey- MSSA, striped – ST22.</p

Molecular characteristics of 94 MRSA isolates.

*<p>MLST and CC was deducted from PFGE pattern after at least one isolate representative of each PFGE pattern was submitted to MLST typing.</p><p>n-numer of isolates,ery- erythromycin, cli- clindamycin, fus- fusidic acid, gen- gentamicin, tri- trimethoprin/sulfamethoxazole, min- minocycline, R-resistance, I- intermediate resistance, S- susceptibility.</p

Molecular relatedness of ST22 isolates in this survey.

<p>Dendrogram of all isolates corresponding to ST22, by deduction from PFGE patterns (see <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0042864#s2" target="_blank">Methods</a>), including MRSA SSC<i>mec</i> IV and V, MSSA and EMRSA-15 isolate as a reference strain.</p

Molecular characterization and relatedness of MRSA isolates carried by parent-child pairs.

<p>Molecular characterization and relatedness of MRSA isolates carried by parent-child pairs.</p

Predictors for <i>S. aureus</i> and MRSA acquisition among children in Gaza, by multivariate analyses.

*<p>Multivariate model for child <i>S. aureus</i> carriage included: being a cat owner, parental <i>S. aureus</i> carriage, day care center attendance, number of household members, child sex and age.</p>**<p>% from <i>S. aureus carriers</i>.</p>$<p>Multivariate model for child MRSA carriage included: child age, sex and parental MRSA carriage.</p>+<p>Models adjusted as described above.</p

Testing IgG antibodies against the RBD of SARS-CoV-2 is sufficient and necessary for COVID-19 diagnosis.

The COVID-19 pandemic and the fast global spread of the disease resulted in unprecedented decline in world trade and travel. A critical priority is, therefore, to quickly develop serological diagnostic capacity and identify individuals with past exposure to SARS-CoV-2. In this study serum samples obtained from 309 persons infected by SARS-CoV-2 and 324 of healthy, uninfected individuals as well as serum from 7 COVID-19 patients with 4-7 samples each ranging between 1-92 days post first positive PCR were tested by an "in house" ELISA which detects IgM, IgA and IgG antibodies against the receptor binding domain (RBD) of SARS-CoV-2. Sensitivity of 47%, 80% and 88% and specificity of 100%, 98% and 98% in detection of IgM, IgA and IgG antibodies, respectively, were observed. IgG antibody levels against the RBD were demonstrated to be up regulated between 1-7 days after COVID-19 detection, earlier than both IgM and IgA antibodies. Study of the antibody kinetics of seven COVID 19 patients revealed that while IgG levels are high and maintained for at least 3 months, IgM and IgA levels decline after a 35-50 days following infection. Altogether, these results highlight the usefulness of the RBD based ELISA, which is both easy and cheap to prepare, to identify COVID-19 patients even at the acute phase. Most importantly our results demonstrate that measuring IgG levels alone is both sufficient and necessary to diagnose past exposure to SARS-CoV-2