What types of drugs have helped reduce the death rate due to tuberculosis infection, and why have they become less effective more recently?

Verified step by step guidance

1. Identify the types of drugs used to treat tuberculosis: The primary drugs used to treat tuberculosis (TB) are isoniazid, rifampin, ethambutol, and pyrazinamide. These drugs are often used in combination to effectively combat the TB bacteria, Mycobacterium tuberculosis.
2. Understand the mechanism of action of these drugs: Isoniazid and rifampin work by inhibiting the synthesis of mycolic acid, an essential component of the bacterial cell wall. Ethambutol interferes with cell wall synthesis by blocking the formation of arabinogalactan, while pyrazinamide disrupts membrane transport and energy production within the TB bacteria.
3. Examine the reasons for the reduced effectiveness of these drugs: The main reason for the reduced effectiveness of TB drugs is the emergence of drug-resistant strains of the TB bacteria. These strains have developed mutations that protect them against the standard drugs, making treatment more difficult.
4. Explore the types of drug resistance: There are two main types of drug-resistant TB: multidrug-resistant TB (MDR-TB), which is resistant to at least isoniazid and rifampin, and extensively drug-resistant TB (XDR-TB), which is resistant to isoniazid, rifampin, any fluoroquinolone, and at least one of three injectable second-line drugs.
5. Discuss the impact of drug resistance on treatment and control: The emergence of drug-resistant TB strains requires the use of second-line drugs, which are often less effective, more toxic, and more expensive than the first-line drugs. This complicates treatment regimens and increases the duration and cost of treatment, while also reducing the overall success rate of TB control programs.