Assessment of humoral and cellular immunity induced by the BNT162b2 SARS-CoV-2 vaccine in healthcare workers, elderly people, and immunosuppressed patients with autoimmune disease.

The development of vaccines to prevent SARS-CoV-2 infection has mainly relied on the induction of neutralizing antibodies (nAbs) to the Spike protein of SARS-CoV-2, but there is growing evidence that T cell immune response can contribute to protection as well. In this study, an anti-receptor binding domain (RBD) antibody assay and an INFγ-release assay (IGRA) were used to detect humoral and cellular responses to the Pfizer-BioNTech BNT162b2 vaccine in three separate cohorts of COVID-19-naïve patients: 108 healthcare workers (HCWs), 15 elderly people, and 5 autoimmune patients treated with immunosuppressive agents. After the second dose of vaccine, the mean values of anti-RBD antibodies (Abs) and INFγ were 123.33 U/mL (range 27.55-464) and 1513 mIU/mL (range 145-2500) in HCWs and 210.7 U/mL (range 3-500) and 1167 mIU/mL (range 83-2500) in elderly people. No correlations between age and immune status were observed. On the contrary, a weak but significant positive correlation was found between INFγ and anti-RBD Abs values (rho = 0.354, p = 0.003). As to the autoimmune cohort, anti-RBD Abs were not detected in the two patients with absent peripheral CD19+B cells, despite high INFγ levels being observed in all 5 patients after vaccination. Even though the clinical relevance of T cell response has not yet been established as a correlate of vaccine-induced protection, IGRA testing has showed optimal sensitivity and specificity to define vaccine responders, even in patients lacking a cognate antibody response to the vaccine.

Herpes simplex virus (HSV) pneumonia in the non-ventilated immunocompromised host: Burden and predictors.

OBJECTIVES: To evaluate burden and predictors of HSV pneumonia among immunocompromised patients not undergoing invasive mechanical ventilation according to a tailored diagnostic algorithm. METHODS: This prospective, observational study included immunocompromised adults with pneumonia non-responding to empirical antibiotic therapy. Bronchoalveolar lavage (BAL) specimens were cultured for bacteria, mycobacteria and fungi. Real-time PCR for Herpesviruses and other microorganisms were performed on BAL and other specimens. Cytological examination of BAL samples was carried out for identification of intranuclear inclusion bodies and immunohistochemical staining for HSV. RESULTS: We enrolled 45 patients (mean age 64.6 years) from January 2015 to June 2016. Nineteen (42.2%) cases tested positive for HSV-1 PCR on BAL. According to our definitions, 11 (24.4%) patients had HSV-1 pneumonia with viral loads ranging between 103 copies/mL and 107 copies/mL. HSV-1 positive throat swab (OR 85.2, 95% CI 5.83-1245.1, P < 0.001) and solid organ transplant (SOT) (OR 53.3, 95% CI 1.37-2072.8, P < 0.03) as underlying condition were found to be independently associated with HSV pneumonia by multivariable analysis. CONCLUSIONS: HSV pneumonia turned out to be relatively common and should be investigated especially in individuals with HSV positive throat swab and SOT. Interventional studies are needed to assess the real clinical impact of HSV pneumonia in immunocompromised patients.

Epidemiological and molecular assessment of a rubella outbreak in North-Eastern Italy.

From January to June 2008, a rubella outbreak involving 111 laboratory confirmed cases occurred in the Friuli Venezia Giulia (FVG) region of North-Eastern Italy. The outbreak occurred initially in two residential homes for young adults disabled mentally and physically. Subsequently, the epidemic spread to the general population. Young adult cohorts were mostly affected and the mean age of the patients was 26.8 years; the majority of cases were male (73.8%), with a mean age of 26.6 years in males and 27.4 in females. Three pregnant women had a primary infection and two had their pregnancies terminated. Genotyping of 16 isolates showed the circulation of RUBV 2B, a genotype originating from Asia and South Africa and now present in Europe. In addition, molecular analysis revealed a well defined space-temporal spread of two viruses showing distinct sequences. A seroepidemiological survey carried out in a city within the same geographical area showed that the proportion of women of childbearing age still susceptible to rubella virus was 5.5%, fairly close to the figure (<5%) expected by 2010.

Group B streptococcus prevalence in pregnant women from North-Eastern Italy: advantages of a screening strategy based on direct plating plus broth enrichment.

AIMS: To assess the sensitivity of a combined selective broth enrichment technique plus selective plating for the detection of group B streptococcus (GBS) colonisation in a large cohort of pregnant women from North-Eastern Italy. METHODS: During 2002-2005, 5020 pregnant women were screened between the 35th and the 37th week of gestation. A lower vaginal sample and a rectal sample were collected and inoculated onto LIM broth and a selective colistin aztreonam blood agar plate (CAP). Direct agar plates were examined after 18-24 hours and, if negative, after 48 hours. LIM broth was subcultured after 18-24 hours onto a Columbia blood agar plate. All colonies suggestive for GBS were submitted to phenotypic identification. RESULTS: 901 Women (17.9%) were positive for GBS. On 728 positive samples, corresponding to patients enrolled between 2003 and 2005, the results of selective direct plating and selective broth enrichment were compared. A total of 561 (77.1% of positive samples, corresponding to 13.9% of patients) were positive on direct selective agar; an additional 167 isolates (22.9% of samples, 4.1% of patients) were recovered from the LIM broth subculture. CONCLUSIONS: The prevalence of GBS carriage in this population-based study is a reliable estimate considering the sensitivity of the microbiological methods used, the rate of attendance of pregnant women to clinical and laboratory settings and the compliance to the protocol. Results confirm that the combination of selective enrichment broth and selective direct plating is a time-saving and sensitive method.

Mother-to-infant transmission of hepatitis C virus: rate of infection and assessment of viral load and IgM anti-HCV as risk factors.

One hundred twenty-six mother-infant couples were studied and 105 exposed babies were monitored for at least 12 months to define the risk of mother-to-infant HCV transmission. Infection occurred in 5 out of 76 infants (6.6%) born to 69 viraemic mothers and in none of 29 born to 26 non-viraemic mothers. Only one child was HCV RNA positive one month after birth, while the remaining children became positive at the 3rd to 4th month. HCV genotypes of the babies matched those of their mothers. No difference was found between women who transmitted the virus and those who did not with regard to age, history of drug abuse, HIV infection, ALT abnormal values, HCV genotype, type of delivery, and breast-feeding. Four out of 5 infected infants were born to mothers with IgM anti-HCV (P = 0.04). The mean viral titre in transmitting women (10(7.2)) was higher than in non-transmitting (10(6.5)), and the proportion of mothers with viral load > or = 10(7) was statistically higher in transmitting than non-transmitting women (P = 0.03). These data show that HCV perinatal infection is a rare event and suggest that IgM positivity and high viral load (> or = 10(7)) in the mother are independent variables correlated with HCV transmission (O.R. = 14.5; 95% CI: 1.3-160.7 and O.R. = 16.3; 95% CI: 1.5-179.9, respectively).