Blisters produced by Paederus sp

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					Blisters produced by
    Paederus sp.
Self-observation by A.E.Beljaev
       July-October 1999
                 How it happened

• From the evening of 15 to the morning of 21 July 1999, I stayed in
  the same room in a hotel in Wad Medani, Sudan.                       2
      How it happened (19 July)
• It was the rainy season, and lots of beetles and bugs were
  entering the room through a ventilation opening, attracted
  by tube lights.
• On 19 July, I noticed a 5 mm whitish lesion on my
  forehead, which was almost painless and healed fast.
• I thought of blister beetles, to which I was exposed in
  Brazzaville in 1992: the symptoms were similar, but much
  less extensive now.
• However, I took no precautions and more than once slept
  with the lights on.

      How it happened (20 July)
• On 20 July (was it the early morning or late evening?), I
  realised in half-sleep that something was disturbing me at
  the left posterior surface of my lower thorax, and thought
  that I might have crushed one of those beetles.
• I just passed my hand between the body and the sheet and
  pulled something out, with the back of my hand.
• I threw it without inspecting and slept again.
• There was a slight burning sensation immediately, but
  nothing in the morning.

    Early development (22 July)
• Some more extended but not very clear burning sensations
  on my back restarted sometimes on 22 July when I was
  busy traveling to Khartoum and, early in the morning of 23
  July, to Cairo.
• I was too busy to look for a mirror to inspect my back.
• There was slight redness of the 1st phalanx of the left
  forefinger; and the lesion was slightly itchy.

Clear manifestations (23-25 July)
• It started to hurt only when I returned to Alexandria on 23
• In the evening of 23 July I had fever up to 38.2C for a few
  hours. I also passed, once, a loose stool (so I am not sure to
  what the fever may be attributed).
• When I finally inspected my back in the mirror, I saw an
  area as if lashed on the left and a few smaller lesions on the
  right side.
• The lesion on the finger became more visible and started
  extending in a central direction.

• I took photographs the next day between 4 and 5 PM.
                                      24/7/99           7
• Sorry, not very focussed, nobody was there to assist me
                                        24/7/99             8
• A new lesion on the 2nd knuckle becomes clear
                                      16:13 24/7/99   9
• The next day, whitish areas appeared.
                                          25/7/99   10
• The hand was hurting, but the lesions on the back did not
  bother me much.                       25/7/99            11
            The climax (26 July)
• The worst was on 26 July. The back of the hand became
  swollen and it hurt even at rest, if the arm was hanging.
• I could, however, sleep, after carefully positioning my
• I try to avoid medicines unless absolutely needed, but on
  25 July I started to apply Burnol, an Indian ointment that
  contains Aminacrine. It soothed a little the pain.
• Ulcerations on the knuckle started on 25 July, but on 26
  they became clearer.

• The worst moment: the back of the hand is swollen,
  especially in the 2nd carpal space. 26/7/99          13
• The white substance looking like pus, is not a pus: it is
  solid and tightly attached to the skin. 26/7/99             14
        Resolution (27-28 July)

• On 27 July, it hurt less and the oedema was receding.
                                        27/7/99           15
27/7/99   16
         Scarring (from 29 July)

• On 29 July, it looked more like a superficial cut.
                                         29/7/99       17
• And hurt only if touched.
                              29/7/99   18
• On 31 July, cicatrisation was in full process
                                         31/7/99   19
31/7/99   20
• On 4 August, it did not hurt, but a tingling sensation was
  there.                                  4/8/99             21
4/8/99   22
• As to the back, it did not disturb me much
                                        4/8/99   23
4/8/99   24
• A possible mechanism of the simultaneous burns on the
  back and the hand.                  4/8/99              25
                A conclusion (1)
• The burns, at least on the left side of the thorax and left
  hand were possibly due to one insect: I crashed it by my
  body and spread the remnants by the back of the palm.
• I did not see the culprit this time.
• I saw the blister beetles many times in Brazzaville during
  an outbreak of dermatitis in 1992.
• At that time I had blisters on the 2nd and 3rd left fingers,
  although do not remember crashing any insect.
• The beetles were identified as Paederus sp. by ORSTOM
  in Brazzaville, and a circular was issued to the expatriates,
  since this outbreak was becoming quite a problem.
                A conclusion (2)
• My lesions then were much the same as now, but less
  extended and not really hurting much.
• I was under impression that time that the lesions would
  appear immediately after the contact.
• What I see now, I was wrong: it may take about 2 days
  before the lesions become clear.
• I praise God that this was not in the eye that the poison has
  been inoculated.
• Otherwise, I would have had a “Nairobi eye”, of which I

                How it happened

• Blister beetle Paederus sp. (Order Coleoptera, Family Staphylinidae,
          genus Staphylinae) are small insects (about 1cm long)     28
                   Paederus sp.
• Blister beetles Paederus sp. (Order Coleoptera, family
  Staphylinidae, genus Staphylinae) are small insects (about
  1cm long).
• They are brightly coloured, with bright blue elytra or cases
  for the wings and red or reddish body. Because of that,
  people of Brazzaville called them “cara”, by the name of a
  popular soccer team whose colours were blue and red.
• At first sight, they do not look like other beetles
  (Coleoptera), because of their slim, elongated body and
  short elytra not covering the length of the abdomen.
• They fly and run rapidly and may accumulate in big
  numbers near the breeding places (shores of streams and
  ponds) or attracted by light.
• 80 days after the exposure, a slight discoloration of the
  area of injury is still visible         8/10/99             30
• particularly on the back.
                              8/10/99   31

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