Clinical Features, Outcome and Prognosis of Human Metapneumovirus (hMPV) Lower Respiratory Tract Infections in Adult Inpatients
Clinical Features, Outcome and Prognosis of Human Metapneumovirus (hMPV) Lower Respiratory Tract Infections in Adult Inpatients
The human metapneumovirus (hMPV) was first described in 2001. It belongs to the paramyxovirus
 family and is genetically close to the Respiratory Syncytial Virus (RSV). hMPV has a seasonal
 epidemic pattern, between January to April. Clinical symptoms of hMPV infection include
 influenza-like illness (fever, asthenia and curvatures) associated with signs of respiratory
 tract infection. The incidence of hMPV infection is higher in children than in adults. In
 child pneumonia, hMPV is the third most frequent isolated pathogen (14 % of the subjects),
 after rhinovirus and RSV. In hospitalized adults, hMPV was detected in 6 to 8% of the
 subjects with lower respiratory tract and in 4 % of subjects with pneumonia.

 Clinical, radiological and biological features, as well as evolution course of hMPV
 infections have been mainly described in children. Clinical presentation of in adult seems
 polymorph, ranging from acute bronchitis or exacerbation of COPD to pneumonia. The frequency
 of viral-bacterial coinfection is unknown. Intensive care unit (ICU) admission may involve
 almost 1 for 10 patients. Elderly and immunocompromised subjects are probably high-risk
 subjects.

 Currently, treatment of hMPV infections is mainly symptomatic. However, several anti-RSV
 drugs that are currently in clinical development have demonstrated an activity against other
 paramyxoviridae in pre-clinical studies. Consequently, it seems necessary to better
 characterize hMPV infections in adult inpatients: presentation, course profile and risk
 factors for morbidity and mortality. These data would help clinicians to identify high risk
 patients, and consequently to choose those who could benefit from coming treatments.

 The French hMPV Study is observational prospective multicenter clinical study. The study
 population includes all consecutive adult inpatients with a community-acquired acute lower
 respiratory tract infection and a mPCR positive for hMPV on any respiratory sample. The
 primary objective is to describe the prognosis. The secondary objectives are i) to
 characterize clinical, radiological and biological features, ii) to describe the hospital
 course and the rate of ICU transfer; in ICU patients, to describe organ failures and
 supports, and iii) to describe the viral and/or bacterial coinfections. The primary endpoint
 is the number of subjects with a poor outcome (defined by the requirement for invasive
 mechanical ventilation and/or the death during the hospital stay).
The human metapneumovirus (hMPV) was first described in 2001. It belongs to the paramyxovirus
 family (paramyxoviridae subfamily). hMPV is genetically close to the Respiratory Syncytial
 Virus (RSV). hMPV has a seasonal epidemic pattern, between January to April. Incubation
 period varies between 4 and 6 days. Clinical symptoms of hMPV infection are close to that of
 RSV, with influenza-like illness (fever, asthenia and curvatures) associated with signs of
 upper and/or lower respiratory tracts infection. The incidence of hMPV infection is higher in
 children than in adults. In a large cohort of children with respiratory illness or fever,
 hMPV was detected in 7 % of outpatients and 6 % of hospitalized children. The annual rate of
 hospitalization associated with hMPV infection has been estimated about 1 per 1000 children
 less than 5 years of age. In child pneumonia, hMPV is the third most frequent isolated
 pathogen (14 % of the subjects), after rhinovirus and RSV. In hospitalized adults, hMPV was
 detect in 6 to 8% of the subjects with a lower respiratory tract and in 4 % of subjects with
 a pneumonia.

 Clinical, radiological and biological features, as well as evolution course of
 hMPV-associated infections have been mainly described in children. Clinical presentation of
 hMPV-associated infection in adult seems polymorph, ranging from acute bronchitis or
 exacerbation of chronic pulmonary diseases (COPD and asthma) to pneumonia. Viral-viral
 coinfections are not exceptional whereas the frequency of viral-bacterial coinfection is
 unknown. Intensive care unit (ICU) admission involved almost 1 for 10 patients. Elderly and
 immunocompromised subjects are probably high-risk subjects. Only one cohort of hMPV-infected
 patients admitted to ICU has been reported. Among the 40 patients, 6 were
 non-immunocompromised and without comorbidity. Factors associated with a poor prognosis were
 not studied.

 Currently, treatment of hMPV-associated lower respiratory tract infections is mainly
 symptomatic. However, several anti-RSV drugs that are currently in clinical development in
 humans, have demonstrated an activity against other paramyxoviridae (hMPV and parainfluenza
 virus) in pre-clinical studies. These anti-RSV drugs should be available for clinicians in
 the next few years. Considering their activity against other paramyxoviridae, clinicians will
 probably attempt to use these anti-RSV drugs in non-RSV paramyxoviridae-associated lower
 respiratory tracts infections in adult inpatients. Consequently, it seems necessary to better
 characterize hMPV-associated lower respiratory tracts infections in adult inpatients:
 clinical, radiological and biological presentation, course profile and risk factors for
 morbidity and mortality. These data would help clinicians to identify high risk patients, and
 consequently to choose those who could benefit from coming treatments.

 The French hMPV Study is observational prospective multicenter clinical study. The study
 population includes all consecutive adult inpatients with a community-acquired acute lower
 respiratory tract infection and a mPCR positive for hMPV on any respiratory sample. The
 primary objective is to describe the prognosis. The secondary objectives are i) to
 characterize the clinical (time from onset to hospital admission, general symptoms,
 respiratory symptoms and signs), radiological and biological features, ii) to describe the
 hospital course and the rate of ICU transfer; in ICU patients, to describe organ failures and
 supports, and iii) to describe the viral and/or bacterial coinfections.
Inclusion Criteria:

 -  Adult (≥18 years old) inpatients with:

 -  an acute lower respiratory tract infection, defined by the presence of two of the
 following criteria in the 5 days preceding hospital admission or during the present
 hospital stay : fever, cough, expectoration, exercise or rest dyspnea, crackles, tubal
 breath, signs of respiratory failure (respiratory rate higher than 30 per minute...),
 thoracic pain, oxygen therapy, mechanical ventilation;

 -  a respiratory mPCR (upper respiratory tracts specimen such as nasopharyngeal swab or
 lower respiratory tract specimen such as tracheal or bronchial aspiration or
 bronchoalveolar lavage) positive for hMPV in the 5 days following hospital admission.

 Exclusion Criteria:

 -  Patient already included in the study.