What testing is recommended for multiple household members with coughing?

Testing Recommendations for Multiple Household Members with Coughing

For multiple household members with cough, tuberculosis (TB) screening is strongly recommended, particularly in high-risk populations, with sputum collection for microscopy and culture being the preferred initial testing approach. 1

Initial Assessment and Testing Strategy

• Active case finding (ACF) is more effective than passive case finding (PCF) when multiple household members present with cough, as it significantly increases TB case detection rates (26.2 vs 6.7 per 100,000) 1
• For household members with cough ≥ 2 weeks, collect sputum specimens for microscopy and culture, especially for those with additional risk factors (elderly, alcoholics, ex-prisoners, immunocompromised individuals, socioeconomically vulnerable) 1
• Chest radiography should be performed for all household contacts with cough, regardless of tuberculin test results 2

Testing Based on Duration of Cough

• Evidence shows no significant difference in TB detection rates when screening is done at 1,2,3, or 4 weeks of cough duration 1
• For children aged ≤14 years with chronic cough (>4 weeks), a systematic approach using validated guidelines is recommended, with chest radiography and spirometry (when age-appropriate) as initial tests 1

Special Considerations for High-Risk Groups

• For people living with HIV (PLWHIV) who have cough, additional WHO-endorsed symptoms (fever, night sweats, hemoptysis, weight loss) should be assessed as they increase the diagnostic sensitivity for TB 1
• In high TB prevalence settings, the Xpert MTB/RIF assay on sputum is more cost-effective than clinical diagnosis alone 1
• Close contacts of any TB case should be considered high priority for evaluation, regardless of the index case's symptoms 2

Testing Algorithm for Multiple Household Members with Cough

1. Initial screening for all household members with cough:

   • Collect sputum specimens for microscopy and culture 1
   • Perform chest radiography 1, 2

2. For individuals with cough ≥ 2 weeks plus any risk factors:

   • Prioritize for immediate testing 1
   • Consider Xpert MTB/RIF testing when available 1

3. For children with cough:

   • Use pediatric-specific cough management protocols 1
   • Base management on cough characteristics and clinical history 1
   • Consider pertussis testing when clinically suspected 1

Testing for Non-TB Causes in Multiple Household Members with Cough

• For acute cough (<3 weeks) affecting multiple household members, consider influenza testing, particularly during flu season 3, 4
• Point-of-care PCR testing for influenza is preferred over rapid influenza diagnostic tests due to higher sensitivity (>95% vs 50-70%) 5
• Consider testing for COVID-19 and influenza coinfection, especially during overlapping seasons 6

Pitfalls and Caveats

• Passive case finding alone fails to identify most individuals with pulmonary TB - in 2000, only 27% of new smear-positive cases were detected through passive means 1
• Screening asymptomatic individuals is cost-effective only in populations with very high TB prevalence 1
• Sputum and nasopharyngeal specimens are more predictive of influenza infection than throat swab specimens (84% and 60% vs 36% positivity rates) 7
• For chronic cough (>8 weeks), consider common non-infectious causes including upper airway cough syndrome, asthma, gastroesophageal reflux disease, and nonasthmatic eosinophilic bronchitis 8