SARS-CoV-2 infection in health care workers during the first 2-years of the pandemic at a cancer hospital in Mexico

BACKGROUND

Health care workers (HCWs) are occupationally exposed to severe acute respiratory syndrome coronavirus (SARS-CoV-2). This study aimed to characterize COVID-19 in HCWs at an oncology hospital in Mexico City over 2-years, identify factors associated with severity, and establish transmission dynamics.

METHODS

This retrospective study included HCWs with confirmed COVID-19. Socio-demographic, clinical, and outcome data were retrieved from March 2020 to March 2022. We compared the proportion of HCWs affected in each wave. A survey on COVID-19 transmission dynamics was conducted in a subgroup.

RESULTS

We included 1,058 workers. The risk of COVID-19 was higher during the Omicron odds ratio (OR 2.10, 95% confidence interval [CI] 1.77-2.50, P < .001). Age ≥41 years old (OR 6.32, 95% CI 2.4-16.62) and being administrative staff (OR 5.51, 95% CI 1.72-17.6) or medical staff (OR 6.82, CI 95% 1.77-26.23), compared to nursing staff, were associated with severity. Vaccination with ≥1 vaccine against SARS-CoV-2 was a protective factor for severe disease (OR 0.04, 95% CI 0.005-0.331).

CONCLUSIONS

This study highlights the impact of COVID-19 on HCWs in a cancer hospital in Mexico City and the impact of vaccination as a protective factor against severity.

Surgical site infection following pancreaticoduodenectomy in a referral cancer center in Mexico

BACKGROUND

Pancreaticoduodenectomy is the standard treatment for resectable periampullary cancer. Surgical site infections (SSI) are common complications with increased morbidity. The study aimed to describe the prevalence, risk factors, microbiology, and outcomes of SSI among patients undergoing pancreaticoduodenectomy.

METHODS

We conducted a retrospective study in a referral cancer center between January 2015 and June 2021. We analyzed baseline patient characteristics and SSI occurrence. Culture results and susceptibility patterns were described. Multivariate logistic regression was used to determine risk factors, proportional hazards model to evaluate mortality, and Kaplan-Meier analysis to assess long-term survival.

RESULTS

A total of 219 patients were enrolled in the study; 101 (46%) developed SSI. Independent factors for SSI were diabetes mellitus, preoperative albumin level, biliary drainage, biliary prostheses, and clinically relevant postoperative pancreatic fistula. The main pathogens were Enterobacteria and Enterococci. Multidrug-resistance rate in SSI was high but not associated with increased mortality. Infected patients had higher odds of sepsis, longer hospital stay and intensive care unit stay, and readmission rate. Neither 30-day mortality nor long-term survival was significantly different between infected and non-infected patients.

CONCLUSIONS

SSI prevalence among patients undergoing pancreaticoduodenectomy was high and largely caused by resistant microorganisms. Most risk factors were related to preoperative instrumentation of the biliary tree. SSI was associated with greater risk of unfavorable outcomes; however, survival was unaffected.

Prevalence of SARS-CoV-2 antibodies in cancer patients and healthcare workers vaccinated with two doses of BNT162b2 or AZD122. A propensity analysis

BACKGROUND

Vaccination is the most effective intervention for reducing the burden of SARS-CoV-2-related disease; however, gaps in knowledge regarding cancer patients (CPs) immune response persist.

OBJECTIVES

To evaluate the humoral response (anti-S antibodies) in CPs and healthcare workers (HCWs) vaccinated with two doses of BNT162b2 or AZD122 vaccines.

MATERIAL AND METHODS

Polyspecific anti-SARS-CoV-2 spike protein (anti-S) antibodies were quantified, and a 1:1 propensity score was used to balance baseline characteristics. Multiple logistic regressions were carried out to evaluate the effect of humoral response-related variables.

RESULTS

One-hundred and twenty-seven CPs (22%) and 439 HCWs (78%) were included. Both populations developed anti-S antibodies in response to vaccination. The mRNA-based vaccine (BNT162b2) was associated with higher odds of having anti-S antibody titers ≥ 1,000 U/mL, while active cancer was related to a lower probability of developing high antibody titers.

CONCLUSIONS

The BNT162b2 vaccine was associated with a higher humoral response. It is necessary for more information and vaccination strategies to be available for immunosuppressed patients in order to select the best biologics for this population based on individual characteristics.

1969. SARS-CoV-2 seroprevalence among patients with cancer and healthcare workers from an oncology referral center during the first year of COVID-19 vaccination in Mexico

Background

Cancer patients (CPs) with COVID-19 have an increased risk of adverse outcomes. In addition, CPs seem to have a lower immune response to SARS-CoV-2 vaccination. This study aimed to evaluate SARS-CoV-2 spike antibodies (anti-S Abs) following COVID-19 vaccination in CPs and healthcare workers (HCWs).

Methods

We conducted a point-seroprevalence study in CPs and HCWs who received a two-dose scheme with either BNT162b2, AZD1222, or Sputnik-V vaccine. We measured anti-S Abs by quantitative immunoassay to assess humoral immune response. Besides, we quantified anti-nucleocapsid antibodies in a subgroup of individuals to determine prior infection. We compared anti-S Abs titers in both groups and stratified by vaccine type, prior infection, and clinical characteristics. We conducted a multivariate logistic regression to determine variables associated with a poor humoral response.

Results

Six hundred forty-one individuals were included: 174 (27%) CPs and 467 (73%) HCWs. The median anti-S Abs titter was higher among HCWs compared to CPs (2568 U/mL vs. 1807 U/mL, p=0.002). Both CPs and HCWs with prior infection had higher anti-S Abs titter (p< 0.001). Regardless of the time since vaccination, a higher proportion of subjects with titers < 250 U/mL was observed in CPs (p< 0.001) (Fig 2). In the multivariate analysis, older age (p=0.036), AZD1222 (p=0.003), and Sputnik-V (p=0.020) were associated with lower humoral response among the entire cohort.

SARS-CoV-2 spike antibody titers among cancer patients and healthcare workers.

Global differences in anti-S Abs titers between CPs and HCWs groups (a) and antibody titers in CPs and HCWs groups stratified by type of received vaccine (b). Abbreviations: CP: Cancer patients, HCW: Healthcare workers.

SARS-CoV-2 spike antibody titers according to time since vaccination among cancer patients and healthcare workers.

Abbreviations: CP: Cancer patients, HCW: Healthcare workers.

Conclusion

In this study, both CPs and HCWs showed an adequate response to vaccination; however, CPs had lower anti-S Abs titers and a faster decline over time. Based on our results, new strategies should be assessed to sustain the humoral response to vaccination and thus decrease the COVID-19 burden among the oncologic population.

Disclosures

All Authors: No reported disclosures.