Study finds human metapneumovirus common in Lagos clinics

Human metapneumovirus (HMPV) is a respiratory germ known to cause serious lower respiratory infections in infants, children, older adults and people with weakened immune systems. A team led by AbdulAzeez Adeyemi Anjorin set out to measure how often HMPV shows up in patients who already have other health problems and who were visiting different clinics in Lagos, Nigeria. In a cross-sectional molecular epidemiological study, the researchers collected nasopharyngeal samples from 150 patients ranging in age from 1 to 88 years old over a two-month window in May and June, 2022. The group focused on clinic patients with underlying conditions and aimed to capture a snapshot of HMPV circulation in this mixed, at-risk population. By testing these real-world clinic samples, the study aimed to reveal not only how common HMPV is in this setting but also how it appears alongside other illnesses and within different age groups, job categories and parts of Lagos. The analysis offers a focused look at HMPV among people already facing other health challenges, information that can help clinicians and public health officials understand where to look more closely for this virus.

Samples from the 150 patients were tested using molecular methods to detect viral genetic material. The laboratory approach used Real-Time Polymerase Chain Reaction after extracting material with an Addbio extraction kit (Germany). The master-mix for the test was prepared using a primer designed targeting the F protein gene of HMPV. Using these methods, the study found that 15.3% (23 out of 150) of the patients were positive for HMPV. Among those positives, the largest share came from the oldest age group: 34.8% (8 of 23) were over 55 years old, while the smallest share, 4.3% (1 of 23), was in the 12–22 year age group. Men accounted for 56.6% (13 of 23) of the positive results. The study also recorded co-infections and co-morbidities: 43.3% (10 of 23) of HMPV-positive patients had malaria, 26.1% (6 of 23) had high blood pressure, 21.7% (5 of 23) had diabetes, 17.4% (4 of 23) had tuberculosis, and 13.3% (3 of 23) had pneumonia. Location and occupation patterns were noted too: Badagry accounted for 39.1% (9 of 23) of positives, Ojo 34.8% (8 of 23), and Alimosho 26.1% (6 of 23). Traders made up 39.1% (9 of 23) of the positive cases, while civil servants, musicians, teachers and the unemployed each made up the lowest share at 4.3% (1 of 23).

The study’s findings highlight important practical points for clinicians and public health planners. The presence of HMPV alongside malaria and chronic conditions like high blood pressure and diabetes suggests two possibilities that the researchers raise: HMPV may worsen existing illnesses, or people living with those conditions may be more likely to pick up HMPV. Either way, the overlap matters because it can change how patients present and how they should be diagnosed and treated. The team behind the work argues for more comprehensive diagnostic approaches in clinics that can look for multiple infections at once, so care teams can recognize when HMPV is part of a patient’s situation rather than attributing symptoms only to a known chronic disease. The authors also stress the need for ongoing epidemiological surveillance, especially among individuals with underlying diseases and protracted illnesses. Regular, targeted monitoring in clinic populations can help detect HMPV activity, guide testing strategies, and inform decisions about managing co-infections in places like Lagos.