National public health surveillance has recently detected an increase in invasive Neisseria meningitidis (N men) disease caused by isolates that are resistant to ciprofloxacin. In February 2024, the CDC addressed this issue in a report Selection of Antibiotics as Prophylaxis for Close Contacts of Patients with Meningococcal Disease in Areas with Ciprofloxacin Resistance — United States, 2024. In Southern California, six cases of invasive disease caused by ciprofloxacin-resistant N men (including one case in Orange County) have been identified in the last year, representing >20% of all N men cases in the region during that time.

Based on this data, and in conjunction with the California Department of Public Health and surrounding counties, OCHCA no longer recommends use of ciprofloxacin for chemoprophylaxis for close contacts of persons with invasive meningococcal disease in Orange County.

• Close contacts of persons with meningococcal disease should receive antimicrobial chemoprophylaxis, regardless of immunization status, due to increased risk for infection. Close contacts include: 1) household members, 2) childcare center contacts, and 3) anyone else directly exposed to an infected patient’s oral secretions (e.g., via kissing, mouth-to-mouth resuscitation, endotracheal intubation or endotracheal tube management) in the 7 days before symptom onset. 
• Ciprofloxacin should no longer be used for chemoprophylaxis for close contacts of persons with invasive meningococcal disease.

The following is the currently recommended chemoprophylaxis regimes for close contacts of persons with invasive meningococcal disease for Orange County:

• While antibiotic sensitive testing (AST) on Neisseria meningitidis is not commonly performed in hospital laboratories, OCHCA strongly encourages microbiologists to contact their preferred reference laboratory about conducting AST testing on isolates Neisseria meningitidis from invasive sites.

• CDC Meningococcal Disease Surveillance – National trends in invasive meningococcal disease.
• CDC - Threshold for Changing Meningococcal Disease Prophylaxis Antibiotics in Areas with Ciprofloxacin Resistance
• CDPH Meningococcal Disease

For questions or concerns, please contact the Communicable Disease Control Division at 714-834-8180.