Disease-causing microorganisms (viruses, bacteria, fungi).

Illnesses caused by pathogens.

Bacteria evolve resistance to antibiotics due to overuse/misuse, making infections harder to treat.

An epidemic that has spread worldwide.

A widespread occurrence of an infectious disease in a community at a particular time.

TB infection where the bacteria is present but not causing symptoms and is not infectious.

TB infection that causes symptoms and is infectious.

A birth defect where a baby's head is smaller than expected, often linked to Zika virus.

Methicillin-resistant Staphylococcus aureus; a type of bacteria resistant to many antibiotics.

A disease transmitted by an arthropod vector, such as a mosquito or tick.

1. Infected mosquito bites human. 2. Plasmodium parasite enters bloodstream. 3. Parasite multiplies in liver and red blood cells. 4. Infected human is bitten by another mosquito. 5. Mosquito becomes infected and transmits parasite to another human.

1. Bacteria are exposed to antibiotics. 2. Some bacteria develop resistance through mutation or gene transfer. 3. Resistant bacteria survive and multiply. 4. Over time, resistant bacteria become dominant.

1. Person with active TB coughs or sneezes, releasing droplets. 2. Another person inhales the droplets. 3. Bacteria infect the lungs. 4. Infection can become latent or active.

1. Mosquito bites infected bird. 2. Virus multiplies in mosquito. 3. Infected mosquito bites human or animal. 4. Virus is transmitted, potentially causing illness.

1. Pathogens contaminate water sources (e.g., sewage). 2. People drink or use contaminated water. 3. Pathogens enter the body. 4. Illness develops (e.g., diarrhea, vomiting).

1. Mosquito bites infected person. 2. Virus multiplies in mosquito. 3. Infected mosquito bites another person. 4. Virus is transmitted, potentially causing illness or birth defects.

Good hygiene, vaccines, clean water, and sanitation can significantly reduce the spread of pathogens.

Drug resistance is increasing, and vaccine development is ongoing.

Latent TB is not infectious; active TB causes symptoms and is infectious.

Poor sanitation and lack of clean water access in developing countries lead to widespread illness.

It leads to harder-to-treat infections, increased illness/death, and spreads easily across borders.

TB is a leading cause of death, especially in developing countries, posing significant public health challenges.

Their transmission dynamics and the impacts of recent outbreaks (SARS, MERS, COVID-19) highlight the importance of understanding viral spread and control.

Mosquito-borne diseases like Malaria, West Nile Virus, and Zika Virus pose significant threats to human health and require comprehensive vector control strategies.

Proper sanitation systems reduce the risk of water contamination and the spread of waterborne pathogens, improving public health outcomes.

Climate change can alter the geographic range and transmission patterns of vectors like mosquitoes, potentially increasing the incidence of diseases like malaria and Zika virus.