# Contact case

> A person exposed to a confirmed case under conditions likely to enable transmission. Subject to medical surveillance and, depending on risk, appropriate isolation.

Canonical source: https://hantatracker.fr/en/glossary/cas-contact/

**Aliases**: contact cases, high-risk contact, close contact, cas contact

A **contact case** is a person who has been exposed to a confirmed case of an infectious disease under conditions likely to enable transmission, without being ill themselves at the moment of identification. For the [MV Hondius](/en/glossary/mv-hondius/) hantavirus episode, France had 22 contact cases identified and hospitalised by 12 May 2026 (passengers of the two key flights of 25 April). Contact case status triggers a **medical surveillance** period whose duration matches the maximum incubation window of the pathogen.

## Operational definition

### Generic criteria

Health authorities (Santé publique France for France, ECDC at European level) define a contact case from several parameters:
- **physical proximity** to the case (distance, duration),
- **environment** of the contact (enclosed space vs. outdoors, ventilation),
- **type of exposure** (presence or absence of protective equipment, direct contact with secretions),
- **infectious period** of the index case (often symptoms ± day −2 to day +10).

For Andes virus, criteria align with Argentinian and Chilean recommendations: prolonged close contact in an enclosed space with a symptomatic case, household sharing, unprotected care.

### Risk levels

Contacts are classified into several levels by exposure intensity:
- **High risk**: household contacts, unprotected carers, prolonged shared enclosed space.
- **Moderate risk**: short exposure or with partial protection.
- **Low risk**: occasional contact in a large ventilated space.

The measures applied (strict isolation, medical surveillance, simple instructions) follow this classification.

## Application to the MV Hondius

### The 22 French contact cases

On 12 May 2026, Minister of Health Stéphanie Rist announced that the 22 French contact cases identified on the two key flights were "hospitalised or being hospitalised":
- **8 contacts** from the Saint Helena → Johannesburg flight of 25 April 2026,
- **14 contacts** from the Johannesburg → Amsterdam flight the same day.

Among them, 3 teenagers accompanied by their parents were placed at **Pitié-Salpêtrière** (Paris 13<sup>th</sup>). One contact case was transferred from home (Concarneau) to **Rennes University Hospital**. Another is hospitalised at **Marseille University Hospital** per the Ministry.

### Legal framework

The decree of 11 May 2026 signed by Prime Minister Sébastien Lecornu governs isolation modalities. Initial hospitalisation lasts about 15 days per the Minister, extended up to 42 days in case of doubt or evolution.

## Difference from "contact tracing"

[Contact tracing](/en/glossary/recherche-de-contacts/) is the **activity** by which health authorities identify everyone exposed to a confirmed case. This activity **produces** contact cases. Once the list is established, each person receives the "contact case" status, with the corresponding measures attached.

## End of status

Contact case status is lifted after the pathogen's **maximum incubation period** with no symptom onset or biological detection. For Andes virus, this period is **42 days**. Beyond that, the risk of developing the disease becomes negligible and the person returns to normal life, without specific surveillance.