Denton County Influenza Surveillance
DCPH Weekly Influenza Surveillance Report for Week 17 (4/21/19 – 4/27/19). This report will conclude influenza reporting in Denton County for the 2018-2019 season.
The CDC issued a health advisory to notify clinicians that influenza activity remains high in the United States, with an increasing proportion of activity due to influenza A(H3N2) viruses, continued circulation of influenza A(H1N1) viruses, and low levels of influenza B viruses.
Low influenza activity was reported in Denton County for week 17. Denton County sentinel providers reported that there were 202 influenza tests performed during week 17, resulting in 3 positive influenza tests (1 Flu A and 2 Flu B) and 1 hospitalization. Syndromic surveillance for influenza-like illness (ILI) in Denton County increased slightly during week 17 when compared to the previous week. Of participating schools, 0.3% of the total school population was absent due to ILI in week 16.
During week 17, influenza activity was reported as sporadic in Texas. The percentage of specimens testing positive for influenza in Texas was 7.0% for week 17. The percentage of visits for ILI in Texas as reported by ILINet providers decreased to 2.7% in week 17 compared to the previous week. The percentage of specimens testing positive for influenza in the US was 5.4% for week 17. The proportion of outpatient visits for ILI in the US in week 17 was 1.8%, which is below the national baseline of 2.2%. The proportion of deaths attributed to pneumonia and influenza (P&I) from the National Center for Health Statistics Mortality Surveillance System for week 16 was 6.3%. This percentage is below the epidemic threshold of 6.9% for week 16.
Healthcare providers should be aware of the following recommendations:
- Clinicians should encourage all patients 6 months of age and older who have not yet received an influenza vaccine this season to be vaccinated against influenza.
- Rapid influenza diagnostic tests (RIDTs) have limited sensitivities and predictive values; negative results of RIDTs do not exclude influenza virus infection in patients with signs and symptoms suggestive of influenza. Therefore, antiviral treatment should not be withheld from patients with suspected influenza, even if they test negative.
- Clinicians should encourage all persons with influenza-like illness who are at high risk for influenza complications to seek care promptly to determine if treatment with influenza antiviral medications is warranted.
- All Hospitalized, Severely Ill, and High Risk Patients with suspected influenza should be treated with antivirals. Prompt treatment with influenza antiviral drugs can reduce serious illness and death. These drugs work best when started soon after influenza symptoms begin (within 2 days), but persons with high-risk conditions can benefit even when antiviral treatment is started after the first two days of illness.