Acute respiratory infections in hospitalized children in Vientiane, Lao PDR – the importance of Respiratory Syncytial Virus

Abstract

The Human respiratory syncytial virus (RSV) is one of the most important viral pathogens, causing epidemics of acute respiratory infection (ARI), especially bronchiolitis and pneumonia, in children worldwide. To investigate the RSV burden in Laos, we conducted a one-year study in children <5 years old admitted to Mahosot Hospital, Vientiane Capital, to describe clinical and epidemiological characteristics and predictive factors for severity of RSV-associated ARI. Pooled nasal and throat swabs were tested using multiplex real-time PCR for 33 respiratory pathogens (FTD® kit). A total of 383 patients were included, 277 (72.3%) of whom presented with pneumonia. 377 (98.4%) patients were positive for at least one microorganism, of which RSV was the most common virus (41.0%), with a peak observed between June and September, corresponding to the rainy season. Most RSV inpatients had pneumonia (84.1%), of whom 35% had severe pneumonia. Children <3-months old were a high-risk group for severe pneumonia, independently of RSV infection. Our study suggests that RSV infection is frequent in Laos and commonly associated with pneumonia in hospitalized young children. Further investigations are required to provide a better overall view of the Lao nationwide epidemiology and public health burden of RSV infection over time.

Etiology of viral respiratory infections in Northern Lao People's Democratic Republic

“…In Luang Prabang in 2010, the incidence of influenza A and B viruses was significantly associated with the rainy season; in 2010, the influenza season presented as a single wave with a peak in September and declined in October‐November, similar to other regions in Lao PDR during the same year . Also RSV was mostly found during the rainy season in Luang Prabang in 2010, similarly to Thailand, Vietnam, Cambodia and to Vientiane in 2009‐2010 and 2014 . In contrast, other respiratory viruses (hAdV, hBoV, hMPV, hCoV‐HKU1, hCoV‐OC43, and PIV3) occurred more often during the dry season, causing respiratory disease mainly when influenza and RSV were less present, while PIV1‐2, hRV, and hCoV‐229E were detected throughout the year, contributing to the background incidence of respiratory infections .…”

Epidemiology of human respiratory viruses in children with acute respiratory tract infection in a 3-year hospital-based survey in Northern Italy

“…HRSV prevailed (67.98%) in younger infants (0 to ≤6 months), while HADV was prevalent in all other age groups studied. Accordingly, HRSV causes severe diseases in young children (Moe et al, 2017;Nguyen et al, 2017;Shi et al, 2017).…”

Respiratory syncytial virus genotypes NA1, ON1, and BA9 are prevalent in Thailand, 2012–2015

“…Although lower prevalence rates have been reported in Korea (2.7%) ( Noh et al, 2013 ) and Brazil (2.4%) ( Bellei et al, 2008 ), RSV infection is reportedly frequent in western China (23.7%) ( Hu et al, 2017 ), the Philippines (19.3%–28.1%) ( Ohno et al, 2013 ; Malasao et al, 2015 ), Vietnam (23%) ( Yoshida et al, 2010 ), Indonesia (23%) ( Simões et al, 2011 ), and Malaysia (18.4%) ( Chan et al, 2002 ). A recent single hospital study in Laos identified RSV in as many as 41% of infected children ( Nguyen et al, 2017 ). Unfortunately, objective comparison of the true regional prevalence of RSV is often hindered by the differences in the RSV detection rates largely due to sample size and the period of surveillance among these studies.…”

“…Variability in RSV infection depends on geographical region, season, and year. In Southeast Asia, RSV incidence appears to peak during the rainy season (July to November), while relatively low rate of infection occurs during the hot and dry months ( Arnott et al, 2011 ; Nguyen et al, 2017 ; Yoshida et al, 2010 ). This is in contrast to the peak incidence in countries with temperate climates whereby RSV infections are more frequent in the winter months ( Gilca et al, 2006 ; Panayiotou et al, 2014 ; Esposito et al, 2015 ).…”