Approach to COVID-19 pandemic management in Madrid. Chronic of a year

After more than a year of pandemic, the international medical community has changed the perception of fear to one of respect for SARS-COV-2. This has been the consequence of the integral study of all the dimensions of the disease, from viral recombinant capacity to transmissibility, diagnosis, care and prevention. This document summarizes the main strategic lines of study and approach to the pandemic in Madrid.

Pharmacokinetic/pharmacodynamic evaluation of the antimicrobial therapy of pneumococcal invasive disease in adults in post-PCV13 vaccine period in Madrid, Spain

The objective of our study was to evaluate by pharmacokinetic/pharmacodynamic (PK/PD) analysis, if the antimicrobials used for the treatment of invasive pneumococcal disease (IPD) in adults, including meningitis, are adequate considering the susceptibility profile of S. pneumoniae in Spain after the implantation of PVC13 vaccine. Pharmacokinetic parameters of benzylpenicillin and cefotaxime were obtained from the literature, and susceptibility data of invasive S. pneumoniae strains recovered in 2017 (post-PCV13 vaccination period) were provided by the Public Health Regional Laboratory of Madrid. We have also studied levofloxacin because it is used to treat pneumococcal pneumonia previously to be diagnosed as bacteremic pneumonia. Monte Carlo simulation was used to estimate the probability of target attainment (PTA) and the cumulative fraction of response (CFR). All doses of benzylpenicillin except 2 mU q6h provide a high probability of treatment success for MIC values ≤ 1 mg/L; 4 mU q4h is even useful for MIC values up to 4 mg/L. This high dose, used for the treatment of meningitis, also provides high probability of treatment success for MIC ≤ 0.5 mg/L. At the susceptibility EUCAST breakpoint (≤ 0.5 mg/L), cefotaxime provides a high rate of PD target achievement, even at the lowest dose (1 g q8h). For meningitis, 2 g q6h ensures probabilities of target attainment ≥90% for MIC up to 1 mg/L. Our study confirms that after the implementation of PCV13 vaccine, the treatment with benzylpenicillin and cefotaxime provides high probability of the therapy success of IPD, including meningitis.

Risk factors and clinical significance of invasive infections caused by levofloxacin-resistant Streptococcus pneumoniae

Purpose

Fluoroquinolones are recommended for the treatment of pneumonia. The recognition of risk factors for invasive levofloxacin-resistant Streptococcus pneumoniae is important for the design of treatment.

Methods

A retrospective review of cases of invasive pneumococcal infections in adults was undertaken. Epidemiologic data, predisposing factors, clinical variables, and outcome were recorded from previously established protocols. Antimicrobial susceptibility was determined by disk diffusion and the Etest method. Serotyping was performed by latex agglutination and Quellung reaction.

Results

Twenty patients with infection caused by levofloxacin-resistant pneumococci [minimum inhibitory concentration (MIC) ≥2 μg/ml] were compared with 102 patients harboring levofloxacin-susceptible strains; 80 % of levofloxacin-resistant pneumococci were resistant to ≥3 antibiotics but susceptible to penicillin. Most levofloxacin-resistant strains (80 %) belonged to serotype 8. In comparison, only 8 % of levofloxacin-susceptible pneumococci belonged to serotype 8. In the multivariate analysis, residence in public shelters [odds ratio (OR) 26.13; p 0.002], previous hospitalization (OR 61.77; p < 0.001), human immunodeficiency virus (HIV) infection (OR 28.14; p = 0.009), and heavy smoking (OR 14.41; p = 0.016) were associated with an increased risk of infection by levofloxacin-resistant pneumococci. Mortality caused by levofloxacin-resistant and levofloxacin-susceptible pneumococci was 35 and 14 %, respectively. Among HIV-positive individuals infected with levofloxacin-resistant pneumococci 44 % died, but only 12.5 % of HIV-positive patients with levofloxacin-susceptible strains died.

Conclusions

We observed the emergence of serotype 8 as the main cause of invasive disease caused by levofloxacin-resistant S. pneumoniae. HIV-positive patients seem to be prone to infection caused by multidrug-resistant serotype 8 and have a high mortality rate.

[Age-dependent seroprevalence of Toscana virus in the Community of Madrid: 1993-1994 and 1999-2000]

OBJECTIVE

The aim of this study was to assess the seroprevalence of Toscana virus (TOSV) in the Community of Madrid.

METHODS

Samples from two serosurveys obtained during 1993-1994 (2262 individuals) and 1999-2000 (1945 individuals) were studied. Samples were tested by ELISA for TOSV IgG detection.

RESULTS

The seroprevalence of TOSV IgG was significantly higher in 1993-1994 (7.2%; 95% CI 6.2-8.4) than in 1999-2000 (5.7%; 95% CI 4.7-6.9) (chi-square, p < 0.05). In both periods, the prevalence increased significantly with age.

CONCLUSION

These results confirm that TOSV has been circulating in the Community of Madrid over the last years.

[Q fever outbreak in an urban area following a school-farm visit]

BACKGROUND AND OBJECTIVE

The aim of this study was to describe an outbreak of Q fever in a group of people (day care centre for mental-handicapped individuals) previously exposed to animals in a school-farm.

PATIENTS AND METHOD

A retrospective cohort study among the 25 mental-handicapped individuals and the 30 workers of the centre was performed. The information about symptoms and signs and antecedents of exposition was obtained by an epidemiological survey and a clinical-epidemiological case definition was established. Serum samples from 29 people (5 mental-handicapped individuals and 24 workers) were processed for serology (Indirect Immunofluorescence against Coxiella burnetii).

RESULTS

Twenty two cases of Q fever were detected. Ten were confirmed by serology (6 of them asymptomatic). More frequent symptoms were fever (100%), anorexia (81.3%), asthenia (68.8%) and non-productive cough (56.3%) among the 16 clinical cases. The risk of acute infection was 8.6 times higher in individuals of the centre that visited the school-farm (95% CI, 1.26-58.27).

CONCLUSIONS

The investigation of the epidemiological antecedents allowed to detect and confirm a Q fever outbreak, to identify the probable source of exposition and to orientate the clinical and serological diagnosis.

Detection of secondary mumps vaccine failure by means of avidity testing for specific immunoglobulin G

The aim of this study was to discriminate between primary and secondary vaccine failure in children with mumps using IgG avidity testing. Thirty-nine serum samples from children with mumps, confirmed by specific IgM, were studied. The patients were grouped according to their immunization status. The secondary immune response was defined by IgG with an avidity index >32%. A secondary response in infected children previously immunized was considered as a secondary vaccine failure. Vaccinated children presented higher IgG titers and IgG avidity than unvaccinated children. The proportion of secondary immune responses in unvaccinated patients was lower than that obtained in previously vaccinated infected patients. Avidity testing can be a useful tool to detect secondary vaccine failure in mumps.

[Foodborne outbreak by Clostridium perfringens in a school dining room]

BACKGROUND AND OBJECTIVE

The purpose was to investigate the etiology and epidemiological characteristics of a food-borne infection outbreak in a school dining room.

SUBJECTS AND METHOD

Retrospective cohort study. Information about gastrointestinal symptoms and the use of the service of the school dining room was obtained. Coprocultures and detection of Clostridium perfringens enterotoxin in stool samples by means of reverse passive latex agglutination were carried out in 7 ill persons. Relative risks (RR) at 95% confidence intervals (95% CI) were calculated.

RESULTS

The attack rate was 17.5% (48/275) and the probability of becoming sick was higher in students who ate at the second shift than in those eating at the first one (RR=13.8; 95% CI: 4.4-43.1). C perfringens enterotoxin was detected in 6 stool samples from patients. A high recount of C perfringens was not observed in those food samples kept frozen after their elaboration.

CONCLUSIONS

The determination of C perfringens enterotoxin in feces allowed to confirm the etiologic agent of the outbreak.