A “major” epidemic in Reunion

Public Health France takes stock of viral circulation in Indian Ocean Reunion. There is a large scale epidemic of leptospirosis and an increase in the circulation of dengue fever.

Written by NP – Friday February 23, 2024 at 2:03 pm

Here are the main points:

Leptospirosis: An epidemic of greater intensity in the last two years.

· Dengue: Circulation is increasing in the south of the island but limited to date.

Conjunctivitis: Increase in cases in private medicine.

· Covid-19: Viral circulation is stable at low levels.

· Flu: Reunion is no longer in a flu pandemic.

Gastroenteritis: Reunion is no longer epidemic.

· Bronchiolitis in children under 2 years of age: Bronchiolitis epidemics are over.

Ongoing epidemics at higher levels than previous years

With the rainy season, climatic conditions are favorable for the persistence of bacteria in water and moist environments, thus increasing the risk of contamination during hazardous activities. Average in the department, with about 2.5 times normal rainfall and average island accumulation just exceeding 1000 mm, January 2024 ranks as the third wettest January in more than 50 years of measurements (Meteo France data). Météo France notes certain similarities with 2018 where the south and south-east zones were also particularly affected.

Assessment up to February 20, 2024: Since January 1, 2024, 54 cases of biologically confirmed leptospirosis occurring during the month of January have been disclosed to ARS. At the same time of the year, 22 cases were reported in 2023 and 18 in 2022.

Increased circulation of dengue

Dengue cases continue to rise in Reunion. The number of cases increased from 16 to 27 between S05 and S06.
More than half of the cases (52%) have been detected in Saint-Joseph, with many active outbreaks.
In week 06, 4 cases were reported in Saint-Paul while none were identified there in S05. This situation is being closely monitored.
Elsewhere on the island, cases were reported in Tampon and Saint-Denis (2 cases each) and Saint-Pierre, La Possession, Saint-Leu, Saint-Louis and Saint-Andre (1 case each).

The first results showed the presence of DENV2 serotype.

Health impact is low with 6 visits to the emergency room (CHU Sud) for syndromes consistent with dengue fever since the beginning of the year and no hospitalizations reported. However, there was a slight increase in the number of consultations for clinically relevant syndromes with dengue fever in community medicine in week 07 (13 in W06 to 18 consultations in W07).

Additionally, there are dengue epidemics in Mauritius and Rodrigues. To date, 10 imported cases have been reported returning from trips to one of these 2 islands. The serotyping result in the person returning from Rodrigues showed DENV2.

Coronavirus: stable and low circulation

In S07, the positivity rate (TP) was stable: 9% in S07 compared to 8% in the previous week. Screening rates were also stable at 56 tests per 100,000 inhabitants in S07 compared to 53 tests per 100,000 inhabitants in S06. TP was generally stable for all age groups except for those aged 45–64 and those over 75 for whom it was increasing.

Flu is not a pandemic

Circulating influenza in virological surveillance S07 is predominantly of the A(H1N1)pdm09 type. The positivity rate was lower with 14% positive tests for influenza virus in S07 compared to 18% in S06. Considering the epidemiological data, the reunion was not in an epidemiological context.

End of bronchiolitis epidemic in Reunion

Emergency room visits for bronchitis in children under 2 years of age were stable in W07 compared to the previous week. In W07, 38 children under 2 years of age consulted the emergency room for bronchiolitis versus 41 in W06.

The number of new hospitalizations was stable in S07 with 19 hospitalizations compared to 22 hospitalizations in S06.