Daniela Bernardes Borges da Silva

Evolutionary pattern of reemerging influenza B/Victoria lineage viruses in São Paulo, Brazil, 1996–2012: Implications for vaccine composition strategy

Since the 1980s, 2 antigenically distinct influenza B lineages have cocirculated in the world: B/Victoria/2/87 (first appeared in the 1980s) and B/Yamagata/16/88 (became predominant in the 1990s). B/Victoria/2/87 isolates were geographically restricted to eastern Asia during 1991–2000. During 2000–2001 and 2001–2002, B/Victoria/2/87 isolates reemerged in North America, Europe, and South America, and then spread globally. During influenza virus surveillance, season 2002, an outbreak of acute respiratory illness, which quickly spread among the population, has been notified by public health authorities living in Araraquara, São Paulo, Brazil. Instituto Adolfo Lutz and Secretariat of Health of São Paulo state teams initiate an investigation towards to describe the pattern of infection in this population temporally and by age and to characterize the strains by virus isolation and hemagglutination inhibition assay. The outbreak lasted approximately 10 weeks; many cases occurred between mid‐August and mid‐September. Children younger than 13 years were the most affected; the elderly were mostly immune to infection. Analysis of the clinical respiratory samples helped in identifying the B/Hong Kong/330/2001 and B/Brisbane/32/2002 subtypes—recent variants of B/Victoria/02/88, a lineage restricted to Southeast Asia until 2001. The Araraquara outbreak confirms the reemergence of the B/Victoria viruses in South America and highlights the importance of monitoring local circulating strains, especially in light of the absence of cross‐protection between antigenically distinct influenza lineages. Based on influenza virus surveillance, public health authorities worldwide should decide whether trivalent vaccines or quadrivalent vaccines (containing both influenza virus B lineages) are to be used in each country. J Med. Virol. 85:1983–1989, 2013.

Shift in the timing of respiratory syncytial virus circulation in a subtropical megalopolis: Implications for immunoprophylaxis

Respiratory syncytial virus (RSV) is the most common cause of severe respiratory infections worldwide, and an important cause of childhood bronchiolitis, pneumonia, and mortality. Although prevention of RSV infection by immunoprophylaxis with palivizumab has proved effective, a precise understanding of the timing of RSV outbreaks is necessary to ensure that infants are protected when RSV is circulating. In this study a consistent shift in the seasonal patterns of RSV circulation in southeast Brazil (São Paulo) is reported based on the analysis of 15 years of viral surveillance. Surveillance was conducted from 1996 to 2010 and involved the collection of samples from children with symptoms of acute respiratory infection. Putative changes in school terms, in the proportion of RSV genotypes infecting children and in the seasonal dynamics of several climatic parameters during the period were also investigated. The results revealed a progression in the timing of RSV seasons, with a shift in the onset and peak of RSV epidemics from 2007 onwards. Although lower rainfall and temperatures were associated with the onset of outbreaks, there was no evidence of changes in climate, school terms or in the relative proportion of genotypes in the period analyzed. These findings have direct implications for improving the prophylactic use of palivizumab, and stress the importance of fine tuning prophylaxis with recent surveillance data. In the case of São Paulo, palivizumab prophylaxis should be initiated earlier than suggested currently. Similar adjustments may be necessary in other regions. J. Med. Virol. 84:1825–1830, 2012.

MOLECULAR CHARACTERIZATION OF INFLUENZA B VIRUS OUTBREAK ON A CRUISE SHIP IN BRAZIL 2012

In February 2012, an outbreak of respiratory illness occurred on the cruise ship MSC Armonia in Brazil. A 31-year-old female crew member was hospitalized with respiratory failure and subsequently died. To study the etiology of the respiratory illness, tissue taken at necropsy from the deceased woman and respiratory specimens from thirteen passengers and crew members with respiratory symptoms were analyzed. Influenza real-time RT-PCR assays were performed, and the full-length hemagglutinin (HA) gene of influenza-positive samples was sequenced. Influenza B virus was detected in samples from seven of the individuals, suggesting that it was the cause of this respiratory illness outbreak. The sequence analysis of the HA gene indicated that the virus was closely related to the B/Brisbane/60/2008-like virus, Victoria lineage, a virus contained in the 2011-12 influenza vaccine for the Southern Hemisphere. Since the recommended composition of the influenza vaccine for use during the 2013 season changed, an intensive surveillance of viruses circulating worldwide is crucial. Molecular analysis is an important tool to characterize the pathogen responsible for an outbreak such as this. In addition, laboratory disease surveillance contributes to the control measures for vaccine-preventable influenza.

Influenza virus A(H3N2) strain isolated from cerebrospinal fluid from a patient presenting myelopathy post infectious

BACKGROUND Neurological involvement during influenza infection has been described during epidemics and is often consistent with serious sequelae or death. OBJECTIVE To investigate the etiologic agent involved in myelopathy post influenza-like syndrome. STUDY DESIGN This investigation focuses on virus isolation from the cerebrospinal fluid (CSF) collected from a 19-year-old male student presenting with clinical diagnosis of myelopathy post influenza-like syndrome. To achieve this goal, different cell cultures and molecular methodologies were carried out. RESULTS Influenza virus A(H3N2) strain was isolated in MDCK cell culture; virus particles were observed under electron microscopy. Phylogenetics analyses showed that the Brazilian influenza A(H3N2) strains were closely related to the A/Perth/16/2009-like. CONCLUSION This study demonstrates that influenza virus A(H3N2) strain was the cause of illness of the students. According to the Brazilian influenza virus sentinel surveillance data A/Perth/16/2009-LIKE (H3N2) strain has predominated during the 2010 influenza virus season in Brasília-DF.

INFLUENZA VIRUS SURVEILLANCE BY THE INSTITUTO ADOLFO LUTZ, INFLUENZA SEASON 2014: ANTIVIRAL RESISTANCE

Neuraminidase (NA) inhibitors (NAIs) are the only antivirals that are effective for prophylaxis and the treatment of seasonal influenza A and B infections. There are currently two NAIs approved in most countries: oseltamivir (Tamiflu; F. Hoffmann La Roche) and zanamivir (Relenza; GlaxoSmithKline plc.). The development of drug resistance is a major drawback for any antiviral therapy, and these specific antiinfluenza drugs are not excluded from this rule. Thus, the proper use of NAIs and worldwide monitoring for the presence and spread of drug resistant influenza viruses are of the utmost importance. The existence of a global surveillance network for influenza, underpinning vaccine strain selection, is a valuable asset when seeking to track the emergence of antiviral resistance.

DIFFERENTIAL DIAGNOSIS OF RESPIRATORY VIRUSES BY USING REAL TIME RT-PCR METHODOLOGY

The emergence of new respiratory viruses including: the Severe Acute Respiratory Syndrome; the coronavirus in 2003 (SARS-CoV); influenza A(H1N1)pdm09, in the human population in the past ten years; the emergence of a new coronavirus identified in a patient presenting severe acute respiratory syndrome who travelled to Saudi Arabia (June, 2012), denominated as Middle East Respiratory Syndrome (MERS-CoV); and laboratory confirmation of three human infections with an avian influenza A(H7N9) virus not previously reported in humans on March 29, 2013, has encouraged scientists to develop diagnostic tests to identify these viruses. The Adolfo Lutz, a Public Health Institute, has been improving its methodology tools in order to provide a timely answer to public health authorities facing acute respiratory disease outbreaks.

Fatal pneumonia due to influenza virus infection diagnosed by conventional and real-time PCR from blood postmortem specimen.

According to the literature, pneumonia diagnosis relies on he assessment of clinical samples such induced sputum, bronhoscopic lower respiratory tract washes or direct lung needle spirates. Sometimes, none of these antemortem specimens are ble to be collected from cases of very severe pneumonia in which he patients die during or soon after admission, leaving an imporant gap in our knowledge of causes of fatal pneumonia.1,3,4 We ould like to inform that two cases of fatal pneumonia, due o influenza virus infection, was diagnosed by conventional and eal-time polymerase chain reaction (PCR) from blood sample postortem. On 29 June 2006 the Institute Adolfo Lutz, São Paulo, Brazil, eceived a postmortem blood sample from a 3-year-old child living s Ribeirão Preto city, state of São Paulo. According to her parents n 24 June 2006 she presented with mild influenza-like symptoms, nd died on 26 June 2006. RNA was isolated from the blood sample by using the ‘QIAamp iral RNA Mini Kit’ (QIAGEN, Santa Clarita, CA, USA) according to he manufacturers instructions. Following influenza virus invesigation by one-step RT-PCR (Reverse – Transcriptase Polimerase hain Reaction) technique using Universal Type A, Universal Type and specific primers to virus strains H1, H3 and H5 kindly proided by the Centers Disease Control and Prevention (CDC), Georgia, tlanta. The postmortem blood sample has confirmed influenza virus 1 strain viraemia by one-step RT-PCR (Fig. 1). This result was onfirmed by CDC. Phylogenetic analysis2 of HA1 gene sequence ndicated that this strain is referred to Clade 1 viruses. This invesigation reinforces the important impact that qualified autopsy ervices could have on the public health. The pathologists must be ncouraged to searching infectious agents in postmortem blood, specially in unexpected deaths. The second postmortem blood sample investigated was ollected from a 7-year-old girl hospitalised presenting with haemrrhagic pneumonia with clinical suspect of Hantavirus, during he influenza pandemic period, July 2009. Taking into account the antavirus negative result, and the information about confirmed (H1N1) pdm09 in the respiratory secretion of her brother, we ecided to perform the CDC-real-time PCR protocol to investigate