Respiratory viruses in children younger than five years old with acute respiratory disease from 2001 to 2004 in Uberlândia, MG, Brazil

Abstract

The main viruses involved in acute respiratory diseases among children are: respiratory syncytial virus (RSV), influenzavirus (FLU), parainfluenzavirus (PIV), adenovirus (AdV), human rhinovirus (HRV), and the human metapneumovirus (hMPV). The purpose of the present study was to identify respiratory viruses that affected children younger than five years old in Uberlândia, Midwestern Brazil. Nasopharyngeal aspirates from 379 children attended at Hospital de Clínicas (HC/UFU), from 2001 to 2004, with acute respiratory disease, were collected and tested by immunofluorescence assay (IFA) to detect RSV, FLU A and B, PIV 1, 2, and 3 and AdV, FLU A and B in 9.5% (36/379), PIV 1, 2 and 3 in 6.3% (24/ 379) and AdV in 3.7% (14/379). HRV were detected in 29. 6% (112/379) Viruses are the most frequent agents that cause acute respiratory infections (ARIs) and are responsible for a considerable percentage of childhood mortality (Williams et al. 2002). In Brazil, some reports from different geographical areas has revealed the viruses as the main cause of respiratory infections, as related in the cities of Fortaleza (Arruda et al. 1991), Rio de Janeiro (Nascimento et al. 1991), São Paulo (Miyao et al. 1999, Vieira et al. 2001), and Curitiba (Tsuchiya et al. 2005.The most important viruses involved in ARI are: respiratory syncytial virus (RSV), influenzaviruses types A and B (FLU A/B), parainfluenzavirus (PIV), adenovirus (AdV), human rhinovirus (HRV), and the human metapneumovirus (hMPV) (Miyao et al. 1999, Kuiken et al. 2003, Tsuchiya et al. 2005). The last one was recently identified by Hoogen et al. (2001).RSV is the main cause of viral lower respiratory tract illness in children (Miyao et al. 1999), particularly in those younger than six months old (mo.) (Queiróz et al. 2002. In addition, RSV infections are responsible for most cases of severe symptoms such as bronchiolitis with recurrent wheezing and pneumonia (Calegari et FLU is a serious public health problem worldwide, were children constitute the age group most affected (Neuzil et al. 2002). Although many infections caused by FLU could be prevented by effective vaccination program, it has been predicted that a pandemic is likely to emerge in a near future (Cox et al. 2003), caused by a virus variant not covered by the current vaccine, requiring, thus, a constant epidemiological surveillance.PIV seems to have pattern of seasonal occurrence and is considered an important cause of respiratory illnesses, particularly among young children (Monto 2002).AdV infections are common in all age groups, causing both hospital-and community-acquired epidemics. Moreover, AdV has been associated with hospitalizations of near-fatal asthma patients (Tan et al. 2003) and with cases of acute otitis media in children younger than two years old (Monobe et al. 2003).HRV is responsible for the majority of common colds during winter, causing upper respiratory infections (Arruda et al. 1991, Savolainen et al. 2003 and is considered a risk factor for acute otitis media (Monobe at al. 2003). ...

Human rhinovirus in the lower respiratory tract infections of young children and the possible involvement of a secondary respiratory viral agent

“…The high frequency of HRV co-infection with RSV has been observed previously (Papadopoulos et al 2002, Paranhos-Baccalà et al 2008, Gerna et al 2009). In our region, the high prevalence of HRV and RSV co-infection may be related to seasonal trends (Costa et al 2006, Oliveira et al 2008); HRV and RSV infections peak concurrently.…”

“…Then, 4 µL of buffer 5x FS, 0.1M DTT, 200 units of Superscript III and 20 µL of water was added to the mix, which was then heated at 55ºC for 1 h. Following cDNA synthesis, the enzyme was heat inactivated at 70ºC for 10 min. Amplification of the HRV nucleotide sequence was performed as previously described by Costa et al (2006). For the first-round of PCR, the cDNA template was amplified with primers 1 and 2 (5'-CGGACACCCAAAGTAG-3').…”

“…RSV A and B and FLU A and B (Stockton et al 1998) were the first viruses tested for, followed by hMPV (Carneiro et al 2009) and PIV 1-3 (Echevarría et al 1998). This order was chosen according to clinical relevance of co-infections in children as determined by the literature (Aberle et al 2005, Calvo et al 2008, Cilla et al 2008) and because of the circulation rate of the most common viruses in the region (Costa et al 2006).…”

Molecular characterization of adenoviruses from children presenting with acute respiratory disease in Uberlândia, Minas Gerais, Brazil, and detection of an isolate genetically related to feline adenovirus

“…RNA was extracted from IFnegative/inconclusive samples with Trizol ® (Invitrogen Corp, Carlsbad, CA), following the manufacturer's instructions. Reverse transcription-PCR (RT-PCR) was used to detect rhinovirus RNA as previously reported (Costa et al 2006). The remainder of each specimen was used for the detection of HAdV.…”

“…In addition, among the 126 specimens that tested negative for respiratory viruses in the IF assay (RSV, PIV 1, 2 and 3, Flu A and B) and for rhinoviruses using RT-PCR (Costa et al 2006), 19 positive samples were obtained using the PCR detection assay. This increased the total rate of HAdV-positive specimens to 7.1% (33/468).…”