1.5 Method
1.5.1 Selecting Sources
A principal vantagem do projeto GFT é proporcionar estimativas quase em tempo real da incidência de surtos da gripe a nível nacional e regional. O GFT fornece uma estimativa precisa diária e pode detetar a ocorrência de surtos de gripe 1-2 semanas antes da publicação dos relatórios dos sistemas de vigilância tradicionais (Carneiro & Mylonakis, 2009) (Cho et al., 2013) (Dukic et al., 2012) (Ginsberg et al., 2009) (Google, 2014) (Kang et al., 2013) (Valdivia et al., 2010).
Os dados das consultas de pesquisa encontram-se disponíveis no website do GFT e qualquer individuo com acesso à internet pode transferir os dados (Cho et al., 2013) (Google, 2014).
Os dados relativos à incidência da gripe podem ser recolhidos mais cedo, de forma mais fácil e com custos mais reduzidos do que os dos sistemas de vigilância tradicionais. Para que os relatórios sejam publicados pelos sistemas de vigilância tradicionais, estes necessitam de 1-2 semanas para que os testes laboratoriais e as análises sejam realizados (Kang et al., 2013).
O GFT não pode substituir os sistemas de vigilância tradicionais mas pode complementá-los (Ortiz et al., 2011) (Valdivia et al., 2010).
Apesar da elevada correlação, o GFT continua suscetível a falsos alertas que podem ocorrer devido ao aumento imprevisto das consultas de pesquisas no motor de busca Google relativas ao SG (Ginsberg et al., 2009).
Uma das desvantagens do GFT é que este não disponibiliza informações epidemiológicas relevantes, como a idade do doente, localização, doença reclamação ou o quadro clínico (Olson et al., 2013).
Ao contrário dos sistemas de vigilância tradicional, o GFT não recolhe os dados demográficos e geográficos (Olson et al., 2013).
5. Conclusão
Todos os anos os vírus da gripe causam infeções graves que resultam em milhões de hospitalizações várias centenas de milhares de mortes, a nível mundial.
A vigilância epidemiológica tradicional da gripe é realizada principalmente por intermédio de redes de Médicos-Sentinela e análises laboratoriais, sistema que, apesar de eficaz, não permite a recolha de dados em tempo real.
Para ultrapassar esta e outras desvantagens dos sistemas de vigilância epidémica tradicionais da gripe, foram criados na Europa os sistemas participativos que são sistemas de vigilância baseados na Internet e que já provaram ser uma boa alternativa para a monitorização e vigilância epidemiológica da gripe.
A nova abordagem com base nas pesquisas de informações através de motores de busca na internet, como o Google Flu Trends, apresenta-se como uma ferramenta promissora para otimizar a detetar de forma antecipada surtos de doenças infecciosas e também, de uma forma mais vasta, uma fonte bastante importante de dados relacionados com as tendências de saúde.
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