Useful and harmful microbes - class-VIII

Dengue fever is a mosquito-borne disease caused by the dengue virus. There is a characteristic skin rash that is similar to measles. It is transmitted by several species of mosquito within the genus Aedes, mainly Aedes aegypti.
Therefore, the correct answer is option A.

Break bone fever is another name for dengue fever. It is a mosquito-borne tropical disease caused by the dengue virus. It is transmitted by several species of the mosquito within the genus Aedes aegypti.
Therefore, the correct answer is option B.

Influenza is commonly known as 'flu' and is a contagious respiratory illness caused by influenza viruses. It can cause mild to severe illness and at times can lead to death. The best way to prevent the flu is by getting a flu vaccination each year.

Aedes aegypti, the principal mosquito vector of dengue viruses is an insect closely associated with humans and their dwellings. People not only provide the mosquitoes with blood meals but also water-holding containers in and around the home needed to complete their development. The mosquito lays her eggs on the sides of containers with water and eggs hatch into larvae after a rain or flooding. A larva changes into a pupa in about a week and into a mosquito in two days. 

The Aedes aegypti mosquito can transmit the viruses that cause dengue fever or breakbone fever.
Psorophora columbiae mosquito is a known vector of encephalitis.
Diseases carried by house flies (musca domestica) include typhoid, cholera and dysentery.
Cimex (bed bug) causes dermatobiasis.

Haemophilus influenzae is a small, pleomorphic bacteria which is the most often cause of pneumonia, a lung infection.
Therefore, the correct answer is option B.

Dengue fever is a mosquito-borne tropical disease caused by the dengue virus. Dengue is spread by several species of a mosquito of the female Aedes type, principally Aedes aegypti. Symptoms include high fever, headache, vomiting, muscle and joint pains, characteristic skin rash, bleeding, low levels of blood platelets and blood plasma leakage. So, the correct answer is 'Female Aedes'.

Penicillin sometimes abbreviated PCN or pen is a group of antibiotics derived from Penicillium fungi. Penicillin antibiotics were among the first drugs to be effective against many previously serious diseases, such as bacterial infections caused by staphylococci and streptococci. Penicillins are still widely used today, though misuse has now made many types of bacteria resistant.

Tourniquet test determines the capillary fragility. It is a clinical diagnostic method to determine a patient's haemorrhagic tendency. It assesses fragility of capillary walls and is used to identify thrombocytopenia (reduced platelet count). This test is used for the diagnosis of dengue fever, also called as breakbone fever.
Therefore, the correct answer is option B.

Dengue is transmitted by the bite of a mosquito infected with one of the four dengue viruses. It is a febrile illness that affects infants, young children and adults with symptoms appearing 3-14 days after the infective bite.
Dengue is not transmitted directly from person-to-person and symptoms range from mild fever, to incapacitating high fever, with severe headache, pain behind the eyes, muscle and joint pain, and rash. There is no vaccine or any specific medicine to treat dengue. People who have dengue fever should rest, drink plenty of fluids and reduce the fever using paracetamol or see a doctor. Dengue is transmitted by several species of mosquito within the genus Aedes, principally A. aegypti.
Severe dengue (also known as dengue hemorrhagic fever) is characterized by fever, abdominal pain, persistent vomiting, bleeding and breathing difficulty and is a potentially lethal complication, affecting mainly children. Early clinical diagnosis and careful clinical management by trained physicians and nurses increase survival of patients.

Common viral diseases include: chickenpox, flu, influenza, herpes, human immunodeficiency virus (HIV/AIDS), human papilloma virus (HPV), mumps, measles and rubella. Bacteria cause disease by secreting or excreting toxins (as in botulism), by producing toxins internally, which are released when the bacteria disintegrate (as in typhoid), or by inducing sensitivity to their antigenic properties (as in tuberculosis). Other serious bacterial diseases include cholera, diphtheria, bacterial meningitis and syphilis.

House flies are strongly suspected of transmitting at least 65 diseases to humans, including typhoid fever, dysentery, cholera, poliomyelitis, anthrax, tularemia, leprosy and tuberculosis. Flies regurgitate and excrete wherever they come to rest and thereby mechanically transmit disease organisms. Dengue is transmitted by mosquito.

There is no vaccine to protect against dengue. Developing a vaccine against the disease is challenging. With four different serotypes of the dengue virus that can cause the disease, the vaccine must immunize against all four types to be effective. 

Diphtheria is caused by a bacterium, Corynebacterium diphtheriae. The actual disease is caused when the bacteria release a toxin into a person's body. Diphtheria bacteria live in the mouth, throat, and nose of an infected person and can be passed to others by coughing or sneezing. Influenza, commonly known as the flu, is an infectious disease caused by the influenza virus. The most common symptoms include: a high fever, runny nose, sore throat, muscle pains, headache, coughing, and feeling tired. These symptoms typically begin two days after exposure to the virus and most last less than a week. 

DPT refers to a class of combination vaccines against three infectious diseases in humans: diphtheria, pertussis (whooping cough), and tetanus. MMR vaccine is a live attenuated viral vaccine used to induce immunity against measles, mumps and rubella. Dengue has no vaccine yet.

Influenza (also known as the flu) is a contagious respiratory illness caused by influenza virus. Typhoid fever is an acute illness associated with fever caused by the Salmonella typhi bacteria. Cholera is an infectious disease that causes severe watery diarrhoea, caused by bacterium called Vibrio cholerae. Diphtheria is caused by the Corynebacterium diphtheriae bacterium.

Diseases caused by viruses are common cold, influenza, AIDS and dengue. Therefore, (b) is the correct answer. Tuberculosis and cholera are caused by bacteria.

The correct answer is 'influenza'

Explanation: It is caused by Pasteurella multocida. Treatment is effective if given in early stage of disease. The nearest Vety officer or paravet of the department should be contacted for treatment and  prevention.

Aedes is a genus of mosquitoes originally found in tropical and subtropical zones but now found on all continents except Antarctica. Some species of this genus (like Aedes albopictus and Aedes aegypti) transmit serious diseases, including dengue fever, yellow fever, eastern equine encephalitis and chikungunya. So, the correct answer is option D.

• Dengue fever is spread through the bite of the female mosquito (Aedes aegypti). 
• The mosquito becomes infected when it takes the blood of a person infected with the virus. After about one week, the mosquito can then transmit the virus while biting a healthy person.
• Hence Dengue fever is spread by Aedes.
• So, the correct answer is 'Aedes'.

• A disease vector is an agent who carries and transmits an infectious pathogen into another living organism.
• Aedes mosquito is known to transmit dengue virus, yellow fever virus, chikungunya virus, Zika virus and Encephalitis(inflammation of the brain).
• It can be recognized by white markings on its legs and a marking in the form of a lyre on the upper surface of its thorax.
• Hence Aedes is a vector of 'Encephalitis and Dengue'.
• So, the correct answer is 'Encephalitis and Dengue'.

• A disease vector is an agent who carries and transmits an infectious pathogen into another living organism.
  
• Aedes aegypti is known to transmit dengue virus, yellow fever virus, chikungunya virus, and Zika virus.
• It can be recognized by white markings on its legs and a marking in the form of a lyre on the upper surface of its thorax.
• Hence Aedes aegypti is a vector for yellow fever and Dengue fever.
• So, the correct answer is 'Both A and B'.

• Arbovirus refers to any viruses that are transmitted by arthropod vectors. Arboviruses can affect both animals, including humans, and plants. 

• Dengue fever is a mosquito-borne tropical disease caused by the dengue virus. Malaria is a mosquito-borne infectious disease caused by protozoa i.e., Plasmodium species. Filariasis is a parasitic disease caused by an infection with roundworms. Amoebiasis is a protozoal infection caused by Entamoeba histolytica.

• Hence, Arbovirus caused dengue fever.

• So, the correct answer is 'Dengue'.

• Dengue fever is a mosquito-borne tropical disease caused by the dengue virus.Dengue is spread by several species of a mosquito of the  Aedes Type, principally A.aegypti.
  
• .Symptoms typically begin three to fourteen days after infection.[2] This may include a high fever, headache, vomiting, muscle and joint pains, and a characteristic skin rash
• Arbovirus is an informal name used to refer to any viruses that are transmitted by arthropod vectors. As dengue is transmitted by an arthropod vector(mosquito) its causative organism is called arbovirus.
• So, the correct answer is 'Arbovirus'.

• Influenza, commonly called 'the flu' is an illness caused by RNA viruses of the family Orthomyxoviridae. For example, Myxovirus influenzae.
  
• The most common symptoms include high fever, runny nose, sore throat, muscle pains, headache, coughing, sneezing, and feeling tired.
• Hence Myxovirus influenzae is the causative organism of influenza.
• So, the correct answer is 'Myxovirus influenzae'.

• Influenza is a viral disease. Influenza virus is of three types, viz; type A, type B and type C. This virus spread even is short distances causing flu-like conditions, fever, runny nose, headache, muscle pain, coughing, etc. 
  
• Typhoid is a disease caused by the bacteria named Salmonella typhi. 
• Dysentery is a gastroenteritis disorder causing diarrhoea. This disorder can be caused by bacteria, viruses, protozoans or parasites. 
• Cholera is caused by the bacteria named Vibrio cholerae. 
So, the correct answer is option B.

Causative agent of cholera is Vibrio cholerae. Vibrio cholerae is a bacterium. 
Tuberculosis is caused by bacteria, Mycobacterium tuberculosis.
Anthrax is caused by bacteria Bacillus anthracis. 
Influenza is caused by influenza virus. 

Pandemic is an epidemic of infectious disease that spreads through human populations across a large region; for instance multiple continents, or even worldwide. The World Health Organization (WHO) has a six-stage classification that describes the process by which a novel influenza virus moves from the first few infections in humans through to a pandemic. This starts with the virus mostly infecting animals, with a few cases where animals infect people, then moves through the stage where the virus begins to spread directly between people and ends with a pandemic when infections from the new virus have spread worldwide and it will be out of control until we stop it. A disease or condition is not a pandemic merely because it is widespread or kills many people; it must also be infectious. 

Use of aspirin during dengue fever is not recommended owing to increased bleeding tendency. Aspirin has an antiplatelet effect by inhibiting the production of thromboxane, which under normal circumstances binds platelet molecules together to create a patch over damage of the walls within blood vessels. Hence drugs such as aspirin and ibuprofen should be avoided as they may increase the risk of haemorrhage. 

Bacillus haemophilus or Bacillus influenzae is a Gram-negative, facultatively anaerobic bacteria that causes influenza disease. It was first described by Richard Pfeiffer during an influenza pandemic. It is usually present in the upper respiratory tract and causes otitis media, epiglottitis, and meningitis.