COVID-19 cases - Weekly review: 19 - 25 April

During the week from 19 to 25 April, the number of people testing positive for COVID-19 continued to decrease slightly from 1,261 to 1,231 (-2.4%), while the number of their identified close contacts also decreased from 2,943 cases the previous week to 2,517 (-14.5%).

It should be noted that the number of PCR tests performed during the week of 19 to 25 April has decreased significantly from 60,364 to 54,044.

183 people reported a positive rapid antigen test.

On 25 April, the number of active infections was relatively stable at 2,622 (compared to 2,692 on 18/04), while the number of people healed increased from 61,666 to 62,962. The average age of those diagnosed as COVID-19 positive decreased to 35.2 years. ​

The number of new deaths also continued to decrease, with 5 deaths related to COVID-19, compared to 8 the previous week. The average age of the deceased is 74 years. (The attached weekly review contains a table of deaths per month and age group).

In the hospitals, there was a decrease in admissions of confirmed COVID patients, with 71 hospitalisations in normal care, compared to 84 the previous week. However, the situation in intensive care continues to be critical: The number of occupied beds increased from 33 to 36. There has been a slight increase in the average age of hospitalised patients (from 56 to 60 years).

The two COVID-19 Consultation Centres (CCCs), located in Kirchberg and Esch-sur-Alzette, have recorded a total of 13,182 visits since their opening, including 495 visits for the week of 19 to 25 April, which is almost identical to the previous week (497).

Positivity rate and incidence rate

For the reference period, the effective reproduction rate (R) remained stable at 0.9, while the positivity rate on all tests performed (prescriptions, Large Scale Testing, contact tracing) increased sightly with 2.28% compared to 2.09% the previous week (average over the week). It should be noted that the positivity rate for tests carried out on prescription, i.e. for people with symptoms, increased from 5.88% to 6.27%.

The 7-day incidence rate decreased to 194 per 100,000 residents. Note that for the week of 12 April, the incidence rate was 201 cases per 100,000 residents over 7 days. Compared to the previous week, the incidence rate has decreased for all age groups, except for the age group 0-15 years (+8%) and 30-44 years (+6%). The most significant decrease is recorded in the age group 75+ years (-21%), followed by the age group 60-74 years (-14%).

The 75+ age group continues to have the lowest incidence rate with 99 cases per 100,000 residents, followed by the age group 60-74 years, with 103 cases per 100,000 residents. Compared to the rest of the population, incidence rates are half as high in people aged 60 and over, who have been the main target of the vaccination campaign so far.

Quarantine and isolation

For the week from 19 to 25 April, 2,841 people were in isolation (-3%) and 2,835 in quarantine (-5% compared to the previous week).


For the 1,231 new cases, the family circle remains by far the most frequent source of transmission of COVID-19 infections with 41.6%, followed the work place (5.4%), education (3.3%) - especially crèches - travel abroad (3.2%) and leisure activities (3.1%). The rate of contamination for which the source is not clearly attributable increased to 39.4%.

Vaccinations: update on the situation

For the week of 19 to 25 April, a total of 14,714 doses were administered. 12,480 people received a 1st dose and 2,234 received a 2nd dose, bringing the total number of vaccines administered until 27 April to 181,908 (1st and 2nd doses).

The follow-up of side effects reported in EudraVigilance following the administration of a COVID-19 vaccine in Luxembourg since the beginning of the vaccination campaign on 28 December 2020, can be consulted via the link COVID-19: monitoring of adverse reactions to vaccines - report from 16.04.2021 ( (French only). It is important to emphasise that the causal link between these adverse events or manifestations post-vaccination is not obvious. These cases are therefore investigated and analysed by the health authorities on an individual basis.

The evolution of the variants

For the week of 12 to 18 April, the population sequencing coverage was 51.6%, well above the optimal rate of 10% recommended by ECDC in order to have an optimal representative sampling.

Regarding the 687 samples carried out for calendar week 15/2021, the following distribution of variants can be observed:

  • The UK variant (B.1.1.7) represents 85.8% of the cases
  • The South African SA variant (B.1.351) represents 8.8% of the cases

During week 15/2021, 5 new cases of the Brazilian variant (P.1), as well as 3 cases of the so-called "double mutant" or "Indian variant" B.1.617 were detected in Luxembourg. All detected cases of the Indian variant are travel-related.

Wastewater monitoring in Luxembourg as part of SARS-CoV-2 

The contamination level of the 13 analysed waste water treatment plants by the LIST (Luxembourg Institute of Science and Technology), during the week of 19 to 25 April indicates an high prevalence of the virus in waste water at national level. An upward trend was observed for this week with an average contamination level similar to that of weeks 13 and 14. This result will have to be confirmed by the analyses performed in the coming weeks.

All CORONASTEP reports are available on the LIST website:

Press release by the Ministry of Health, the Laboratoire national de santé (LNS) and the Luxembourg Institute of Science and Technology (LIST)

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