Pertussis IgG, in Visit Clinic

Pertussis IgG positive means IgG antibodies against Bordetella pertussis are detected in the blood. It usually reflects past infection or vaccination rather than active disease; very high or rising titres can suggest recent infection. Accurate interpretation depends on symptom timing and vaccination history, and acute cases may need PCR or culture. Discuss results with your clinician for next steps.

IgM and IgG against Bordetella pertussis differ in timing and interpretation. IgM appears early in acute infection, peaking in the first few weeks and indicating recent exposure. IgG rises later, persists longer, and reflects past infection or vaccination; a single IgG measure can’t reliably distinguish recent versus remote immunity without paired sera or rising titres. Clinicians use both for timing diagnosis.

Pertussis IgA positive means IgA antibodies against Bordetella pertussis were detected, suggesting recent or ongoing whooping cough infection. IgA indicates a mucosal immune response that rises within weeks of infection and can help diagnose subacute cases or when PCR is negative. Results must be interpreted with clinical context and may be confirmed by PCR, culture, or paired serology.

The definitive confirmatory test for pertussis is culture of Bordetella pertussis from a nasopharyngeal swab or aspirate, though sensitivity falls after the first two weeks. PCR on nasopharyngeal specimens is commonly used as a rapid, highly sensitive diagnostic in early disease. Serologic testing (anti-pertussis toxin IgG) can help confirm infection in later stages.

If you test positive for pertussis, a clinician will prescribe antibiotics (usually a macrolide) to reduce contagiousness; you should isolate until 5 days of effective treatment. Close contacts may be offered prophylactic antibiotics. Supportive care (fluids, rest, cough control) is advised; infants, pregnant women, or anyone severely ill may need hospitalization. Public-health authorities may be notified to limit spread.

No. Pertussis (whooping cough) and tuberculosis (TB) are different infections. Pertussis is caused by Bordetella pertussis, causes violent coughing fits with a “whoop,” is treated with macrolide antibiotics, and prevented by DTaP vaccination. TB is caused by Mycobacterium tuberculosis, produces chronic cough, weight loss, night sweats, and requires prolonged multi‑drug therapy and different public‑health measures.