Measuring COVID-19 vaccines effectiveness (VE)
Cohort study to measure COVID-19 vaccine effectiveness among health workers
Question/population:
Health workers in participating hospitals, eligible for vaccination, with no contraindication to receive COVID-19 vaccine
Primary objectives:
- To measure product-specific COVID-19 vaccine effectiveness (VE) amongst hospital health workers eligible for vaccination against all laboratory-confirmed SARS-CoV-2 infection
Secondary objectives (depending on sample size)
- To measure COVID-19 VE:
- against symptomatic laboratory-conformed COVID-19 infection
- against asymptomatic laboratory-confirmed COVID-19 infection
- against severe laboratory-confirmed COVID-19 infection
- by time since vaccination
- by different age groups
- by different high-risk comorbidities
- previous SARS-CoV-2 infection
- by HW occupation and/or ward
- patient-facing vs. non-patient-facing HWs
- in individuals who have been partially vaccinated (one dose for most COVID-19 vaccines) compared to those who are fully vaccinated (two doses for most COVID-19 vaccines)
Measuring COVID-19 vaccines effectiveness (VE)
Protocol for a case-control study
Question/ population:
severe acute respiratory infections (SARI) hospitalisations associated with laboratory-confirmed SARS-CoV-2
Primary objective:
- To measure overall COVID-19 vaccine effectiveness (CVE) against laboratory-confirmed SARS-CoV-2 in hospitalised SARI patients belonging to the target group(s) for COVID-19 vaccination.
Secondary objectives:
- To estimate overall and product-specific CVE against laboratory-confirmed SARS-CoV-2 requiring hospitalisation among SARI patients in vaccination target groups by:
- age group
- sex
- risk group (e.g. specific chronic conditions)
- time since vaccination
- in persons who have received one dose of vaccine compared to those who have received two doses
- specific SARS-CoV-2 genetic variant(s)
- To estimate CVE for more severe outcomes (e.g. ICU admission, or in-hospital mortality)
- To identify potential factors that may modify CVE: chronic medical conditions, influenza vaccination, living in a long-term care facility (LTCFs), receiving statins or other long-term medication (depending on availability of these data in the participating country), and higher risk of exposure to SARS-CoV-2.
Population-based age-stratified seroepidemiological investigation protocol for COVID-19 infection
Question/ population:
Virus infection in the general population
- To measure the seroprevalence of antibodies to COVID-19 in the general population by sex and age group, in order to ascertain the cumulative population immunity; and
- To estimate the fraction of asymptomatic, pre-symptomatic or subclinical infections in the population and by sex and age group.
Secondary objectives, such as, but not limited to:
- To determine risk factors for infection by comparing the exposures of infected and non-infected individuals;
- To contribute to determine the case fatality ratio; and
- To contribute to an improved understanding of antibody kinetics following COVID-19 infection.
The First Few COVID-19 X cases and contacts transmission investigation protocol (FFX)
Question/ population:
Cases and close contacts in the general population or
can be restricted to semi-close settings (like households, health care settings, schools).
The primary objectives are to provide descriptions or estimates of :
- clinical presentation of COVID-19 infection and course of associated disease;
- secondary infection rate (SIR) and secondary clinical attack rate of COVID-19 infection among close contacts (overall, and by key factors such as setting, age and sex, for various end-points);
- serial interval of COVID-19 infection;
- symptomatic proportion of COVID-19 cases (through contact tracing and laboratory testing); and identification of possible routes of transmission.
- identification of possible routes of transmission
The secondary objectives are to support the estimation of:
- the basic reproduction number (R0) of COVID-19 virus;
- the incubation period of COVID-19; and
- the preliminary COVID-19 infection and disease-severity ratios (for example, case‑hospitalization ratio [CHR] and case-fatality ratio [CFR]).
Household transmission of COVID-19 investigation protocol (HH)
Question/ population: Cases and close contacts in household setting
Primary objectives:
- To better understand the extent of transmission within a household by estimating the secondary infection rate for household contacts at an individual level, and factors associated with any variation in the secondary infection risk.
- To characterize secondary cases including the range of clinical presentation, risk factors for infection, and the extent and fraction of asymptomatic infections
- To characterize serologic response following confirmed COVID-19 infection
Protocol:
Prospective study of a cohort of health workers)
Question/ population:
All health workers in a health care setting in which patient(s) with a laboratory-confirmed COVID-19 infection are receiving care
——————————————–
Protocol:
Protocol for a case-control study
Question/ population:
Health workers exposed to COVID-19 patients
Primary objectives:
- To better understand the extent of human-to-human transmission among health workers by estimating the secondary infection rate[1] for health worker contacts at the individual level.
- To characterize the range of clinical presentations of infection and the risk factors for infection among health workers.
- To evaluate the effectiveness of infection prevention and control measures among health workers.
- To evaluate the effectiveness of infection prevention and control programmes at health facility and national level.
Secondary objectives such as, but not limited to:
- To determine the serological response of health workers with symptomatic and possibly asymptomatic COVID-19 infection;
- To characterize the duration and severity of COVID-19-associated disease among health workers.
———————————————————————————–
The primary objective of this case-control study among health workers is:
- to characterize and assess the risk factors for SARS-CoV-2 infection in health workers exposed to COVID-19 patients.
The secondary objectives of the study are:
- to evaluate the effectiveness of current COVID-19 IPC measures among health workers;
- to describe the range of clinical presentation for SARS-CoV-2 infection in health workers, including disease duration and outcome; and
- to determine serological responses in health workers with confirmed SARS-CoV-2 infection following exposure to COVID-19 patients, and in those exposed to COVID-19 patients but without SARS-CoV-2 infection.
Schools and other educational institutions transmission investigation protocol for COVID-19
Question/ population:
Students and staff of schools and other educational institutions with a laboratory confirmed case of COVID-19
The overall aim is to gain an understanding of the transmission dynamics of COVID-19 infection among cases and contacts within schools and other educational institutions.
Primary objectives are:
- to estimate infection rates for overall and secondary COVID-19 infections in this context
- to estimate the secondary clinical attack rate of COVID-19 in this setting
- to estimate the fraction of asymptomatic COVID-19 infections within schools and other educational institutions
- to describe the epidemiological and clinical characteristics of primary and secondary cases of COVID-19
- to identify potential risk/protective factors associated with the COVID-19 infection risk.
Secondary objectives are:
- to estimate the incubation period of COVID-19 and the duration of infectiousness and of detectable shedding;
- to estimate the serial interval of COVID-19 infection in this setting;
- to estimate the reproduction numbers: R0 and R of COVID-19 in this setting; and
to characterize the serological response following confirmed COVID-19 infection
Protocol:
A prospective cohort study investigating maternal, pregnancy and neonatal outcomes for women and neonates infected with SARS-CoV-2
Question/ population:
pregnant or recently pregnant women (and their neonates), both infected with SARS-CoV-2 (exposed) and not infected with SARS-CoV-2 during pregnancy (unexposed).
Primary objectives:
- To analyze if SARS-CoV-2 infection in pregnant women increases the risk of adverse outcomes (as per outcomes 1-4 above) as compared to pregnant women who are not infected with SARS-CoV-2.
- To estimate the risk of mother-to-child-transmission of SARS-CoV-2 virus during pregnancy, intrapartum, postpartum (including during breastfeeding) among mother-neonate pairs with confirmed SARS-CoV-2 infection in pregnancy
- To describe viral presence and persistence in amniotic fluid, placenta, cord blood, fetus, neonate as well as in breast milk and other bodily fluids (urine, feces, vaginal fluids)
- To characterize the clinical course and disease spectrum of COVID-19 during pregnancy
Secondary objectives:
- Estimate the cumulative incidence of asymptomatic, subclinical, and clinically apparent SARS-CoV-2 infection during pregnancy, as assessed by seroconversion or a positive RT-PCR test during and following pregnancy.
- Measure the frequency of detectable RNA for SARS-CoV-2 by RT-PCR and IgG/IgM antibodies in neonates born to women infected with SARS-CoV-2 during pregnancy.
- Characterize the signs, symptoms, and disease course of neonates who have SARS-CoV-2 infection following childbirth from a pregnant woman infected with SARS-CoV-2
Optional secondary objective:
To determine if disease severity and disease characteristics of COVID-19 are different in pregnant women compared to non-pregnant women of reproductive age.
Protocol:
Surface sampling of SARS-CoV-2: A practical “how to” protocol for health care and public health professionals
Question/ population:
For environmental surfaces
Primary objectives:
- To assess the extent and persistence of surface contamination of SARS-CoV-2; and
- To identify environmental surfaces and fomites that may play a role in onward transmission of COVID-19.
Secondary objectives such as, but not limited to:
To characterize of the sequence diversity of SARS-CoV-2 in environmental samples, as capacity and resources permit.