BUGS DRUG 3 Flashcards
Picornoviridae
4 genera
Subgroups
\+ sense ssRNA, nonenveloped, icosohedral
Genera
1)Enterovirus (intestinal and lymphoid infection) fecal oral spread
- Poliovirus
-Cocksackie A and B
- Echovirus
2) Rhinovirus
3) Hepatovirus
4) parechovirus
Poliovirus
Infects:
- Peyers patches and tonsils (fecal oral spread and resp secretions)
- motor neurons (paralytic poliomyelitis)
- risk paralysis increases as one gets older
- primarily anterior horn, some presynaptic destruction (no sensory)
Disease course: mild illness -> +- aseptic meningitis -> +- paralytic poliomyelitis
Vaccine:
- salk: formalin-killed injected, IgG made. No paralytic polio assoc.
- Sabin: Attenuated. Oral, spread to contacts. IgA and IgG made. Occasionally paralytic polio virulance is picked up, should NOT be used in immunocompromised.
Most common cause of aseptic meningitis in the USA
Enteroviruses .
=cocksackie A/B, echovirus, new enteroviridae
Cocksackie A
Mild illness: Attack rate near 100%!
- Herpangina: fever, sore throat, small red based vesicles back of throat
- Hand, foot, mouth: mild illness, malaise, fever, oral vesicles, small tender lesions hands, feet, buttocks.(Enterovirus 71 can also cause)
Cocksackie B
Pleurodynia: Fever, headache, lower pleuritic pain
-Cock B = 50% of viral myocarditis/pericarditis. Can be mild->severe. Worse when younger. 10% progress to dilated cardiomyopathy, the rest recovers.
Common cold offenders
rhinovirus and coronaviridae
Famousness of coronaviridae
Common cold + SARS.
SARS
fever, myalgia, chills - >dry cough -> severe resp involvement -> ARDS
Enterovirus considerations
Different serotypes cause different clinical manifestations.
-Aseptic meningitis, hemorrhagic conjunctivitis, MOST COMMON cause of fever/rash (exanthums) in children summer/fall.
Enteroviurs 71 -> Hand foot mouth
HAV
more mild hepatitis. Vaccine available
Pinworm (Enterobius vermicularis)
Most common Helminth infection in the USA
- fecal/oral transmission
- larvae hatch in small intestine
- mature in cecum
- lay eggs in perianal area
Mild Symptoms:
- asymptomatic
- allergy to secretions/pruritis + 2ndary bacterial infection w/fatigue
- granuloma’s in vagina
- rare penetration of bowel wall and migration
Tx; Mebendazole (vermox)
whipworm
Appears whiplike
-eggs require soil to mature and become infectious
Symptoms
- asymptomatic
- anemia
- abdominal pain
- dysentery
- growth retardation if severe infection >200 worms
Tx; Mebendazole (vermox)
Ascaris Lumbricoides
1billion infected, huge 30cm.
Tropics and southern mountainous USA
Life cycle: Egg ingested -> hatch in duodenum -> penetrate intestinal wall into BV’s -> liver/heart/pulmonary circulation -> grow/molt in alveoli -> crawl up/coughed/swallowed (3mo after ingestion) ->mate/lay eggs in intestines
Symptoms:
- pneumonitis
- intestinal obstruction
- migration to bile duct/pancreas/liver
- malnutrition in children
Dx:Eggs in stool
Tx; Mebendazole (Vermox)
hookworm
BLOOD SUCKERS
Some Southeastern USA prevalence
Life Cycle:
Larvae hatch/mature in stool -> penetrate human skin as FILARIFORM LARVAE -> lung -> trachea ->swallowed/mature and attach to intestinal wall (suck blood and eat protein) and mate-> live 5-18yrs depending on species
Symptoms:
- Asymptomatic unless high worm burden
- anemia/protein deficiency if poor nutrition and/or high worm burden
Tx; Mebendazole
nematode is what?
roundworm
platyhelminthe is what?
flatworm
