Vaccine effectiveness against COVID-19: A test negative case-control study in Tunisia, August 2021

BACKGROUND

In response to the COVID-19 pandemic, multiple vaccines to protect against COVID-19 disease have been developed rapidly. Precise estimates of vaccine effectiveness (VE) vary according to studies design, outcomes measured and circulating variants. The aim of this study was to evaluate the anti-covid-19 vaccine effectiveness in Tunisia.

METHODS

We conducted a matched case-control study from 2nd to 15th August 2021. Cases and controls were subjects over 60 years of age, selected from the National testing database, regardless vaccine status. A standardized questionnaire was administered for cases and controls to collect information about vaccination status. For cases, vaccination status was defined based on the number of doses received before becoming ill and excludes doses received during the previous two weeks. For matched controls, a reference date based on the case's date of illness onset was defined in order to look at the control's vaccination status before its corresponding case became ill. The odds-ratio was calculated using simple conditional logistic regression. The VE (95 % confidence intervals) was calculated as (1 - odds ratio for vaccination) × 100 %.

RESULTS

A sample of 977 matched peers for age and Gender, were included between August 2, and August 15, 2021. The overall vaccine effectiveness (VE) was 70 % [95 % CI 62.8-75.8 %]. Among our sample, 68.1 % of the male population and 56.4 % of the female population were vaccinated with a VE of 73 % [95 % CI 62.9-80.3 %] and 67 % [95 % CI 55.8-75.3 %] respectively, regardless vaccine scheme (complete or incomplete). VE was higher for the age group [60-70 years[ (72.3 % [95 % CI 62.8-79.3 %]). VE was 77.6 % [95 % CI 70.9-82.8 %] to prevent both symptomatic and asymptomatic forms of the disease. Moreover, in prevention from severe forms (treated with oxygen-therapy or admission to an Intensive-care-unit) VE was 86.6 % [95 % CI 75.6-92.7 %] and 98.4 % [95 % CI [79.2-99.8 %] in prevention from COVID-19 deaths with a complete anti-Covid vaccination scheme.

CONCLUSION

The results of our study showed that the anti-Covid-19 vaccines used in Tunisia are efficient to prevent both SARS-COV-2 infections and severe forms related to the disease. This study provided important data on the performance of vaccines in real-world settings that guide decisions about vaccine sustained use.

Primary breast sarcomas: A 13 case-series study treated in university hospital in central Tunisia over a 25-year period

AIM

To retrospectively study the therapeutic modalities of primary breast sarcomas in view of the data of a local Tunisian experience.

METHODS

It is a monocentric, descriptive, retrospective study including 13 cases of primary breast sarcoma treated over a period of 25 years (1995-2020) in the oncological radiotherapy department of a university hospital in Sousse, Tunisia.

RESULTS

In our study, 13 cases of non-metastatic breast sarcomas that has been identified, divided into ten cases of phyllodes sarcomas and three cases of non-phyllodes sarcomas.Surgically, all our patients had a mastectomy. Among them, seven underwent a lymph node procedure: five underwent axillary lymph node dissection, and two others had primary axillary lymph node biopsy. For the adjuvant treatment, all the patients included in our study received radiotherapy and seven received chemotherapy. Local recurrence occurred on the operative scar in one patient after completion of radiation therapy. Metastatic relapse was described in five patients. The time to onset of metastases varied between two months and five years. Nevertheless, a complete remission was noted in 6 patients with a follow-up varying from four years to 20 years. Two patients were lost to follow-up.

CONCLUSION

Breast sarcomas remain a very rare entity of aggressive tumors.The therapeutic approach is poorly codified. For this reason, the therapeutic decision should always be discussed in a multidisciplinary assessment.

Control of Acinetobacter baumannii outbreak in intensive care units in Tunisia, 2022

Introduction

Acinetobacter baumannii is an emerging pathogen that is increasingly resistant to antibiotics and is mainly responsible for pneumopathy in fragile patients. This germ is frequently responsible for epidemics in hospitals. We aimed to describe the steps of the investigation of an outbreak of Acinetobacter baumannii affected our hospital, the measures implemented and the follow-up of the actions.

Methods

Following alerts issued by the microbiology department concerning 5 swabs detecting Acinetobacter of the same strain and the same antibiotic resistance profile in 3 different departments of intensive-care units (ICU), a team of the prevention and healthcare security department went onsite for an investigation in the hospital.

Results

We identified five cases with identical strains of multi-resistant Acinétobacter. The field visit allowed to identify some deficiencies in professional practices. All the patients were hospitalized in ICU (medical and surgical). The synoptic table showed that there was an overlap of hospitalization periods.A crisis cell was set up to validate, coordinate and implement control measures in accordance with CTINILS recommendations. Indeed, we proceeded to a technical isolation of the cases in their hospitalization sector, reinforced the basic hygiene and bio-cleaning measures and sensitized the medical and paramedical. Given that the three ICU departments shared the same medical staff during night shifts, the assumption that the germ was carried by the caregivers was the most likely hypothesis. We proceeded with a swab of the elements of the environment in the services concerned. Results showed that Acinetobacter was found on the nursing cart (visibly clean). A training about bio-cleaning and hygiene standard precautions is programmed.

Conclusions

Continuous surveillance, continuous hygiene trainings, combined with a rapid reaction capacity in case of identification of a new case, is essential to control the spread of nosocomial germs.

Key messages

• Multidrug-resistant Acinetobacter baumannii (MRAB) is an emerging cause of intensive care unit (ICU) outbreaks.

• Enhanced infection control measures limited the outbreak.

[Clinical and epidemiological features of COVID-19-related deaths in Tunisia before the emergence of VOCs (March 2020-February 2021)]

Introduction

the purpose of this study was to describe the clinical and epidemiological features of COVID-19-related deaths in Tunisia notified at the ONMNE (National Observatory of New and emerging Diseases) between 2^nd March 2020 and 28^th February 2021 and to compare COVID-19-related deaths recorded in Tunisia with the international data.

Methods

we conducted a national prospective longitudinal descriptive study of data collected from the National Surveillance System of SARS-CoV-2 infection of the ONMNE, Ministry of Health. All COVID-19-related deaths that occurred in Tunisia between March 2020 and February 2021 were included in this study. Data were collected from hospitals, municipalities and regional health departments. Death notifications were collected from multiple data sources (triangulation): The Regional Directorate of Basic Health Care, the ShocRoom (Strategic Health Operations Center), public and private health facilities, the Crisis Unit of the Presidency of the Government, the Directorate for Hygiene and Environmental Protection, the Ministry of Local Affairs and the Environment, as part of the follow-up of confirmed cases by the ONMNE team, positive RT-PCR / TDR post mortem results.

Results

during this study, 8051 deaths were recorded, corresponding to a proportional mortality of 10.4%. The median age was 73 years, with an interquartile range of 17 years. Sex-ratio (M/F) was 1.8. The crude death rate was 69.1/100 000 inhabitants and fatality rate was 3.5%. The analysis of the epidemic curve showed 2 peaks of deaths on 29^th October 2020 and 22^nd January 2021, with 70 and 86 deaths notified respectively. The spatial distribution of mortality showed that the southern Tunisian region had the highest mortality rate. Patients aged 65 and over were most affected (73.7% of cases) with a crude mortality rate of 570.9/100,000 inhabitants and a fatality rate of 13.7%.

Conclusion

prevention strategy based on public health measures must be reinforced by the rapid deployment of anti-COVID-19 vaccination, especially for people at risk of death.